Front load pressure jacket system with syringe holder and light illumination

ABSTRACT

The fluid injection apparatus for use with a syringe includes an injector and a pressure jacket assembly associated with the injector. The injector includes a housing defining a central opening and a drive piston extendable through the central opening for imparting motive forces to a syringe plunger disposed within the syringe. The pressure jacket assembly includes a pressure jacket and at least one support arm associated with and extending outward from the housing. A syringe retaining member is attached to the at least one support arm. The syringe-retaining member defines a syringe receiving slot for receiving at least a portion of the syringe. A light source is located on the support arm and faces the pressure jacket for illuminating the syringe. The syringe includes an alignment flange defining a bulged air bubble viewing window (see A). The alignment flange is used to properly orient the syringe in the pressure jacket.

BACKGROUND OF THE INVENTION

[0001] 1. Technical Field of the Invention

[0002] This invention relates generally to pressure jacket systems forsecuring a syringe to an injector, to syringes for use with pressurejackets systems, and to methods of loading syringes in and removingsyringes from pressure jacket systems. More specifically, the inventionrelates to front-loading pressure jacket systems and methods forallowing front loading and removal of syringes therefrom, and tosyringes of special construction for use with, for example, pressurejackets.

[0003] 2. Description of Related Art

[0004] In the medical field, patients are often injected with fluids inprocedures such as angiography, computed tomography (CT), and magneticresonance imaging (MRI). In such procedures, which require controlledinjection of relatively large volumes of fluid into a patient, acatheter is used as a conduit for the fluid, which is connected to thesyringe(s) by a connector tube. The syringe(s) is mounted on a motorizedinjector having an injector head.

[0005] For compatibility with injectable fluids, syringes may be made ofglass or polymeric materials, such as polypropylene, with a certainminimum wall thickness. The thickness is critical as typical pressuresof up to 1200 p.s.i. (i.e., in angiographic procedures) are used toinject the fluids into a patient.

[0006] Pressure jackets are known in the art in at least two varieties,breech or rear loading and front loading, for substantially enclosingand retaining syringes while in use. A pressure jacket serves to limitradial expansion of a syringe, which may lead to bursting or to leaks ofthe pressurized fluid around the seal(s) of the syringe plunger. Anotherfunction of a pressure jacket is to prevent forward motion of thesyringe. For example, a force of 2400 pounds is typically required torestrain the forward motion of a 150 ml syringe with a cross section of2.0 in² at 1200 p.s.i.

[0007] U.S. Pat. No. 4,677,980, the contents of which are incorporatedherein by reference, discloses an angiographic injector apparatus inwhich syringes are rear loaded into a pressure jacket of the injector.More specifically, the apparatus comprises a rotatable turret thatcarries a pair of the pressure jackets and which is rotatable so thatwhen one of the pressure jackets, into which a syringe has been rearloaded, is in an injection position, the other pressure jacket is in aposition in which an associated syringe may be rear loaded.Subsequently, when injection of contrast media from the first syringe iscompleted, the turret is rotated to move the first syringe to anunloading-loading position, with the second pressure jacket and thesecond syringe concurrently being moved into the injection position.

[0008] A disadvantage of rear loading pressure jacketed injectors isthat, after an injection, the patient tubing typically must bedisconnected from the syringe before the syringe may be extracted fromthe rear of the pressure jacket and discarded. Not only does thisoperation expend valuable operator time but fluids, such as contrastfluid and blood, may drip or spill from the syringe or the tubing afterthe tubing is removed from the syringe thereby creating a potentiallyunsafe or hazardous condition. Additionally, fluid spilled duringloading and purging of air from the syringe may migrate inside thepressure jacket and the injector and require cleaning.

[0009] Motivated at least in part by this concern, front-loadinginjectors (pressure jacketed and non-pressure jacketed injectors) havebeen developed. U.S. Pat. Nos. 5,300,031; 5,779,675; and 5,800,397, forexample, disclose front-loading pressure jacketed injector systems andU.S. Pat. No. 5,383,858 discloses front-loading pressure jacketed andnon-pressure jacketed injector systems. The contents of U.S. Pat. Nos.5,300,031; 5,779,675; 5,800,397; and 5,383,858 are incorporated hereinby reference.

[0010] U.S. Pat. No. 5,300,031 discloses various embodiments of apressure jacketed injector system wherein a syringe is loaded into andremoved from an injector pressure jacket through an opening provided inthe front end of the pressure jacket. To retain the syringe within thepressure jacket, for example during an injection operation, the frontend of the syringe is locked to the front end of the pressure jacket.

[0011] U.S. Pat. No. 5,779,675 also discloses various embodiments offront-loading pressure jacketed injector systems. In a number ofembodiments, for example as shown in FIGS. 12-16 of the '675 patent, oneor more retaining plates or walls preferably supported by one or morearms or rods retain a syringe within the pressure jacket. The retainingplates or walls are preferably moved between open and closed positionsto allow syringes to be inserted into and removed from the pressurejackets.

[0012] While front-loading pressure jacketed injector systems are knownin the art, improvements in the design of such pressure jacketedinjector systems and also in the design of syringes used in bothpressure jacketed and non-pressure jacketed injector systems are andcontinue to be highly desirable.

SUMMARY OF THE INVENTION

[0013] The present invention relates generally to a fluid injectionapparatus for use with a syringe having an injection section with aninjection neck. The fluid injection apparatus comprises a housingdefining an opening and a drive piston extendable through the openingfor imparting motive forces to a syringe plunger disposed within thesyringe. The fluid injection apparatus further comprises a pressurejacket assembly associated with the housing for securing the syringeduring an injection procedure. The pressure jacket assembly comprises apressure jacket associated with the housing and aligned with theopening, at least one support arm associated with and extending outwardfrom the housing, and a syringe retaining member associated with the atleast one support arm. The syringe retaining member defines a syringereceiving slot for receiving at least the injection neck of the syringeand viewing at least a portion of the injection section. The at leastone support arm is movable, preferably selectively, between a firstposition wherein the syringe retaining member prevents removal of thesyringe from the pressure jacket and a second position wherein thesyringe is removable from the pressure jacket. In a preferredembodiment, the pressure jacket assembly is a front-loading pressurejacket assembly.

[0014] The pressure jacket may have a distal end defining a syringereceiving opening for receiving the syringe and a proximal endassociated with the housing. The pressure jacket assembly may furthercomprise a faceplate associated with the injector, for example connectedto the housing. The faceplate may define a passage aligned with theopening and through which the injector drive piston is extendable. Theinjector drive piston may have an axially directed light source forilluminating the syringe.

[0015] The pressure jacket may be removably associated with thefaceplate. The pressure jacket assembly may further comprise a couplingmember adapted to removably asssociate the pressure jacket with thefaceplate. The pressure jacket may be removably associated with thecoupling member by a threaded connection therewith. The coupling membermay be removably associated with the faceplate by a bayonet socketconnection. The pressure jacket may be removably associated with thefaceplate and is preferably movable axially with respect to thefaceplate.

[0016] Alternatively, the faceplate may be considered to be part of theinjector instead of the pressure jacket assembly. In particular, thefaceplate may be removably or permanently connected to, or integrallyformed with the injector housing. In addition, the coupling member maybe configured and used as an adapter to mount different or varying typesof pressure jackets and/or syringes to or on the injector. To that end,the fluid injection apparatus of the present invention may be providedwith one or more coupling members for adapting the injector for variouspressure jackets and/or syringes.

[0017] The at least one support arm may comprise at least one lightsource positioned to illuminate the syringe received in the pressurejacket. The at least one light source may located on the syringeretaining member and positioned to illuminate the syringe, in additionto or as an alternative to locating the at least one light source on theat least one support arm. The at least one support arm preferablyextends laterally along a longitudinal side of the pressure jacket inthe first position. Preferably, the pressure jacket is made ofsubstantially clear plastic. The pressure jacket may comprise alight-diffusing device for diffusing light from a light source externalto the pressure jacket.

[0018] The at least one support arm may comprise a pair of support armsadapted to support the syringe retaining member. For example, thesupport arms may pivotally support the syringe retaining member. Thesupport arms each have a distal end and a proximal end. The fluidinjection apparatus may further comprise an axle assembly adapted toconnect the proximal ends of the support arms together in the housing.The axle assembly is preferably configured to selectively move thesupport arms between the first and second positions. The support armsmay extend laterally along longitudinal sides of the pressure jacket inthe first position. At least one of the support arms preferably has atleast one light source positioned to illuminate the syringe received inthe pressure jacket. The at least one light source may be located on thesyringe retaining member and positioned to illuminate the syringereceived in the pressure jacket.

[0019] The axle assembly may comprise an axle linkage extending betweenthe proximal ends of the support arms. The axle linkage preferablycomprises a base member and two outward extending axles. The base membermay define a recess through which the drive piston is extendable andretractable in any position of the support arms.

[0020] The proximal ends of the support arms preferably each define acircular aperture for rotatably receiving a pair of circular members,respectively. The circular members are preferably supported on the axlelinkage. The central axis of the axle linkage may be offset from therotational axis of the circular members for converting rotationalmovement of the circular members to translational movement of thesupport arms. The axle linkage may be supported on the faceplate by apair of support brackets. The circular members may be associated withthe support brackets, respectively, to limit the rotational movement ofthe circular members in the circular apertures. The circular members mayeach comprise a ball detent adapted for a mating connection with detentopenings defined in the support brackets for providing at least atactile indication that the support arms are set in the first position.

[0021] The proximal ends of the support arms are preferably associatedwith the faceplate to guide the movement of the support arms between thefirst and second positions. To this end, the proximal ends of thesupport arms may define guide tracks and the faceplate may have crosspins associated therewith, which cooperate with the guide tracks,respectively, to guide the movement of the support arms between thefirst and second positions. The faceplate may further comprise a pair ofball detents adapted for a mating connection with detent openingsdefined in the proximal ends of the support arms, respectively, toprevent uncontrolled movement of the support arms to the secondposition.

[0022] Another embodiment of the fluid injection apparatus comprises ahousing and a pressure jacket assembly associated with the housing forsecuring the syringe during an injection procedure. The pressure jacketassembly may comprise a pressure jacket associated with the housing, atleast one support arm extending outward from the injector housing, andat least one light source associated with the at least one support armand positioned to illuminate the syringe received in the pressure jacketand, in particular, fluid and possibly any air bubbles in the fluid. Thelight source may be a plurality of light emitting diodes, amini-fluorescent light bar, a fiber-optic bed, and the like.

[0023] The at least one support arm may comprise a pair of support arms.At least one of the support arms may have the at least one light source.The support arms may be movable between a first position extendinglaterally along longitudinal sides of the pressure jacket and a secondposition depending below the pressure jacket, such that with the supportarms in the first position the syringe is illuminated substantiallyalong a central axis thereof during an injection procedure.

[0024] To diffuse the light entering the syringe through the wall of thepressure jacket, a light-diffusing device may be associated with thepressure jacket. The light-diffusing device may be associated with theinner or outer walls or surfaces of the pressure jacket, or disposedbetween the inner and outer walls or surfaces of the pressure jacket. Inone embodiment, the light-diffusing device may be a lens attached to theinner surface of the pressure jacket and extending longitudinally alongthe inner surface of the pressure jacket. In another embodiment, thelight-diffusing device may be an etched area formed on the inner surfaceof the pressure jacket and extending longitudinally along the innersurface of the pressure jacket. In further embodiment, thelight-diffusing device may be a light-diffusing strip made, for example,of white polycarbonate material. The inner wall or surface of thepressure jacket may define a groove, which may extend longitudinallyalong the inner surface. The light-diffusing strip may be disposed inthe groove for diffusing light passing through the wall of the pressurejacket. The groove may be trapezoidal shaped in cross section and havetwo inward facing projections for retaining the light-diffusing strip inthe groove.

[0025] A further embodiment of the fluid injection apparatus of thepresent invention includes one or more of a syringe, a syringe plungermovably received in the syringe, an injector, and a pressure jacketassembly. The syringe has a cylindrical body with an injection sectioncomprising a conical portion and an injection neck. The conical portiondefines an alignment flange or tab member. The alignment flangepreferably operates as an orientation “key” that is received within thesyringe receiving slot in the syringe retaining member of the pressurejacket assembly. The syringe plunger is located in the cylindrical bodyand has a coupling end with a pair of rigid or flexible coupling membersdefining a slot therebetween, as shown and described in U.S. Pat. Nos.4,677,980 and 5,873,861, the contents of which are incorporated hereinby reference. With the slot substantially aligned with the alignmentflange, the alignment flange provides an indication, such as a visualindication, of the orientation of the slot. When the “key” or alignmentflange is aligned with or received in the syringe receiving slot, thesyringe plunger is substantially oriented with the drive piston of theinjector (i.e., a desired mounting position) such that the drive pistonand syringe plunger may be correctly and securely engaged.

[0026] The injector comprises a housing defining an opening and a drivepiston extendable through the central opening for imparting motiveforces to the syringe plunger disposed within the syringe body. Thepressure jacket assembly is associated with the housing for securing thesyringe during the injection procedure. The pressure jacket assemblycomprises a pressure jacket associated with the housing and aligned withthe opening, at least one support arm associated with and extendingoutward from the housing, and a syringe retaining member associated withthe at least one support arm. The syringe retaining member defines asyringe receiving slot for receiving the injection neck of the syringeand viewing at least a portion of the injection section. The syringeretaining member may further define at least one opening spaced radiallyoutward from the syringe receiving slot for viewing the injectionsection, for example to observe whether fluid or air is present in thesyringe body. The at least one support arm is movable, preferablyselectively, between a first position wherein the syringe retainingmember prevents removal of the syringe from the pressure jacket and asecond position wherein the syringe is removable from the pressurejacket. The alignment of the alignment flange with the syringe receivingslot in the syringe retaining member automatically orients the couplingmembers in a desired mounting position with the slot therebetweenoriented to receive the drive piston.

[0027] The conical portion of the syringe body preferably furthercomprises a light-sensitive fluid dot as an optical aid 215. Thealignment flange may extend outward sufficiently from the conicalportion to be grasped by a user of the syringe and used as a handle formanipulating the syringe. The coupling members may each have an inwardprojecting engagement arm for engaging the drive piston. The couplingmembers may be flexible coupling members.

[0028] The present invention also relates generally to pressure jacketsfor receiving syringes used in fluid injection procedures. The pressurejacket of the present invention comprises an elongated body andlight-diffusing means or device provided on the body. The elongated bodyis formed of substantially clear plastic material. The light-diffusingmeans or device is adapted to diffuse light passing therethrough emittedby an externally located light source. The light-diffusing means ordevice may be a lens, which may be provided on an inner surface of thebody and extend longitudinally along the inner surface of the body. Thelens may also be provided on the outer surface of the body or disposedbetween the inner and outer surfaces of the body. Alternatively, thelight-diffusing means or device may be an etched area on the body. Theetched area may be provided on the inner surface of the body and extendlongitudinally along the inner surface of the body. A groove may bedefined in the inner surface of the body. The light-diffusing means ordevice may a light-diffusing strip disposed in the groove. The groovemay extend longitudinally along the inner surface of the body. Thelight-diffusing strip may be white polycarbonate material. The groovemay be trapezoidal shaped in cross section and have two inward facingprojections for retaining the light-diffusing strip in the groove.

[0029] Additionally, the present invention relates generally to syringesfor use with pressure jackets, preferably front-loading, pressurejackets, and fluid injection apparatuses incorporating pressure jackets,preferably front-loading pressure jackets. The syringe of the presentinvention is generally comprised of a body, a plunger, and an alignmentflange. The body is preferably a cylindrical main body. A conicalportion is connected to the main body and a discharge outlet isconnected to the conical portion. The plunger is movably disposed withinat least a portion of the main body. The alignment flange is disposed onand extends outward from at least a portion of the conical portion. Thealignment flange defines a hollow area therein. The hollow area may beoperable to retain air bubbles therein. The syringe may be disposable(i.e., single use) or reusable for injecting a liquid medium into thebody of a patient

[0030] In another embodiment, the syringe comprises a body having adistal end and a proximal end. The body has an injection section at thedistal end and an expansion section at the proximal end. The injectionsection and expansion section are connected by a center section or mainbody of relatively uniform outer diameter. The wall thickness of thebody preferably narrows to a reduced wall thickness at the expansionsection such that an inner diameter of the expansion section is largerthan the inner diameter of the center section for allowing the expansionsection to expand when a syringe plunger is disposed in the expansionsection.

[0031] The reduced wall thickness preferably allows the expansionsection to expand to an outer diameter no greater than approximately theouter diameter of the center section when the plunger is disposed in theexpansion section. The body may be made of a deformable materialpermitting the expansion section to expand to an outer diameter nogreater than approximately the outer diameter of the center section whenthe plunger is disposed in the expansion section. The body may be madeof substantially clear plastic such as polypropylene, such aspolyethylene terephthalate (PET), polyethylene, polycarbonate, and thelike.

[0032] An outer surface of the body may be tapered or stepped inwardtoward a central axis of the body and an inner surface of the body maybe tapered or stepped outward away from the central axis of the body toform the reduced wall thickness. Alternatively, only the inner surfaceof the body may be tapered or stepped outward away from the central axisof the body to form the reduced wall thickness. An additionalalternative is to only taper or step the outer surface.

[0033] The plunger is preferably movably received in the body and seatedfor storage in the expansion section of the syringe body. The plungermay have a coupling end comprising a pair of coupling members defining aslot therebetween. The slot is preferably substantially aligned with thealignment flange such that the alignment flange provides an indicationof the orientation of the slot when loading the syringe into a pressurejacket, such as a front-loading pressure jacket.

[0034] Yet another embodiment of the syringe comprises a cylindricalbody and a plunger movably received in the cylindrical body. The bodyhas an injection section at a distal end and an expansion section at aproximal end. The plunger may be seated for storage in the expansionsection. The injection section and the expansion section are connectedby a cylindrical center section or main body of relatively uniform outerdiameter. The injection section comprises a conical portion and aninjection neck. The conical portion preferably comprises an alignmentflange extending outward from at least a portion of the conical portion.The plunger has a coupling end preferably with a pair of flexiblecoupling members defining a slot therebetween for engaging a drivepiston of an injector. The slot is preferably substantially aligned withthe alignment flange such that the alignment flange provides anindication, such as a visual indication, of the orientation of the slotto facilitate engagement of the flexible coupling members with the drivepiston of the injector. The coupling members may each have an inwardfacing or projecting engagement arm for engaging the drive piston of theinjector. The wall thickness of the body preferably narrows to a reducedwall thickness at the expansion section such that an inner diameter ofthe expansion section is larger than the inner diameter of the centersection for allowing the expansion section to expand under radialoutward force exerted by the plunger.

[0035] Furthermore, the present invention relates generally to a methodof loading a syringe to an injector. The syringe comprises a cylindricalmain body, a conical portion connected to the main body, and a dischargeoutlet connected to the conical portion. A plunger is movably disposedwithin at least a portion of the main body. An alignment flange isdisposed on and extends outward from at least a portion of the conicalportion. The injector comprises a pressure jacket assembly comprising apressure jacket associated with the injector, at least one support armassociated with and extending outward from the injector, and a syringeretaining member associated with the at least one support arm. Thesyringe retaining member defines a syringe receiving slot for receivingthe discharge outlet of the syringe. The at least one support arm ismovable between a first position wherein the syringe retaining memberprevents removal of the syringe from the pressure jacket and a secondposition wherein the syringe is removable from the pressure jacket. Themethod may comprise the steps of: inserting a proximal end of thesyringe into the pressure jacket; aligning the alignment flange on thesyringe with the syringe receiving slot in the syringe retaining member;and moving the at least one support arm and the syringe retaining memberfrom the second position to the first position. The method may furthercomprise the steps of moving the at least one support arm and thesyringe retaining member from the first position to the second position,and removing the syringe from the pressure jacket. Further, the methodmay comprise the steps of connecting the plunger to the drive piston ofthe injector, and advancing the drive piston to move the plunger withinthe syringe. Moreover, the method may comprise the step of retractingthe plunger within the syringe with the drive piston.

[0036] Another embodiment of the fluid injection apparatus of thepresent invention generally comprises a housing and a pressure jacketassembly associated with the housing. The housing defines an openingthrough which a drive piston of the injector is extendable for impartingmotive forces to a syringe plunger disposed within the syringe. Thepressure jacket assembly associated with the housing secures the syringeduring an injection procedure. The pressure jacket assembly generallycomprises a pressure jacket associated with the housing and aligned withthe opening, at least one support arm pivotally associated with andextending outward from the housing, and a syringe retaining memberpivotally associated with the at least one support arm. The syringeretaining member defines a syringe receiving slot for receiving theinjection neck of the syringe and viewing at least a portion of theinjection section. The at least one support arm is movable between afirst position wherein the syringe retaining member prevents removal ofthe syringe from the pressure jacket and a second position wherein thesyringe is removable from the pressure jacket.

[0037] The syringe retaining member may be pivotal between a syringeretaining position cooperating with the injection section of the syringeand a pivoted position disengaged sufficiently from the injectionsection to allow the at least one support arm to pivot to the secondposition. The at least one support arm may comprise a proximal endpivotally associated with the housing and a distal end extending outwardfrom the housing. The proximal end may have an increased cross sectionrelative to the distal end such that an upward moment is created aboutthe pivotal association with the housing for maintaining the at leastone support arm in the first position. The at least one support armpreferably extends laterally along a longitudinal side of the pressurejacket in the first position.

[0038] A spring means (i.e., a spring) or like device may be providedbetween the syringe retaining member and the at least one support armfor orienting the syringe retaining member with respect to the at leastone support arm. The spring may be adapted to bias the syringe retainingmember to a position substantially perpendicular to the at least onesupport arm. The spring may be a leaf spring, a coil spring, a torsionspring, and the like. The spring may be positioned in a cavity definedin the syringe retaining member adjacent the distal end of the at leastone support arm.

[0039] The at least one support arm may be pivotally connected to thefaceplate associated with or connected to the housing. The pressurejacket may be removably associated with the faceplate. The pressurejacket assembly may further comprise a coupling member adapted toremovably associate the pressure jacket with the faceplate. The pressurejacket may be removably associated with the coupling member by athreaded connection. The coupling member may be removably associatedwith the faceplate by a bayonet socket connection. The pressure jacketmay be removably associated with the faceplate and movable axially withrespect to the faceplate.

[0040] The at least one support arm may comprise a pair of support armseach having a proximal end pivotally associated with the housing and adistal end extending outward from the housing. The proximal ends of thesupport arms may have increased cross sections (i.e., increased mass)relative to the distal ends such that an upward moment is created aboutthe pivotal associations with the housing for maintaining the supportarms in the first position. The syringe retaining member may bepivotally connected to the distal ends of the support arms andinterconnect the distal ends. A pair of springs (i.e., spring means) orsimilar device may act between the support arms, respectively, and thesyringe retaining member for orienting the syringe retaining member withrespect to the support arms. The springs or similar device may beadapted to bias the syringe retaining member to a position substantiallyperpendicular to the support arms. The springs may be positioned inrespective cavities defined in the syringe retaining member adjacentdistal ends of the support arms.

[0041] The pressure jacket has a distal end defining a syringe receivingopening for receiving the syringe. The distal end of the pressure jacketmay define a beveled portion forming an acute angle with a central axisof the pressure jacket. With the at least one support arm in the firstposition, the syringe retaining member may be pivotal between a syringeretaining position wherein a syringe facing side of the syringeretaining member cooperates substantially with the injection section andprevents removal of the syringe from the pressure jacket, and a pivotedposition pivoted away from the injection section and toward the beveledportion for allowing the at least one support arm to pivot to the secondposition. The beveled portion may define an acute angle of about 60° orless with the central axis of the pressure jacket.

[0042] The support arms may comprise at least one light sourcepositioned to illuminate the syringe received in the pressure jacket andextend laterally along longitudinal sides of the pressure jacket in thefirst position. The syringe retaining member may comprise at least onelight source positioned to illuminate the syringe received in thepressure jacket. The pressure jacket is preferably made of substantiallyclear plastic, such as polypropylene, polyethylene, and polycarbonate,as indicated previously. The pressure jacket may further comprise alight-diffusing device for diffusing light from a light external to thepressure jacket.

[0043] Further details and advantages of the present invention willbecome apparent from the following detailed description when read inconjunction with the drawings, wherein like part are designated withlike reference characters and distinct embodiments are designated withprimed reference characters.

BRIEF DESCRIPTION OF THE DRAWINGS

[0044]FIG. 1 is an exploded perspective view of a fluid injectionapparatus in accordance with an embodiment of the present invention;

[0045]FIG. 2 is an exploded perspective view of a syringe and a pressurejacket assembly associated with the fluid injection apparatus of FIG. 1;

[0046]FIG. 3 is a perspective and partially cutaway view of the syringeassociated with the fluid injection apparatus of FIG. 1;

[0047]FIG. 4 is a cross sectional view taken along a longitudinal axisof the fluid injection apparatus of FIG. 1;

[0048]FIG. 5 is an exploded perspective view of the pressure jacketassembly of the fluid injection apparatus of FIG. 1;

[0049]FIG. 6 is an exploded perspective view of the pressure jacketassembly of FIG. 5 viewed from an opposite end;

[0050]FIG. 7 is a perspective view of the pressure jacket assembly ofFIGS. 5 and 6 showing a syringe support structure of the pressure jacketassembly in a syringe-engaged position supporting a syringe;

[0051]FIG. 8 is a perspective view of the pressure jacket assembly ofFIGS. 5 and 6 showing the syringe support structure of the pressurejacket assembly in a syringe-disengaged position;

[0052]FIG. 9 is a cross sectional view of a portion of a support arm ofthe syringe support structure showing the support arm in a firstposition;

[0053]FIG. 10 is a cross sectional view showing the support arm of FIG.9 in an intermediate position;

[0054]FIG. 11 is a cross sectional view showing the support arm of FIG.9 in a second, pivoted position;

[0055]FIG. 12 is a perspective view of another embodiment of the fluidinjection apparatus and pressure jacket assembly of the presentinvention showing the syringe support structure of the pressure jacketassembly in the syringe-engaged position supporting a syringe;

[0056]FIG. 13 is a perspective view of the pressure jacket assembly ofFIG. 12 showing the syringe support structure in the syringe-disengagedposition;

[0057]FIG. 14 is an exploded perspective view of the pressure jacketassembly of FIGS. 12 and 13;

[0058]FIG. 15 is a side view of the pressure jacket assembly of FIG. 12;

[0059]FIG. 16 is a side view of the pressure jacket assembly of FIG. 12showing a syringe retaining member of the syringe support structure in apivoted position;

[0060]FIG. 17 is a side view of the pressure jacket assembly of FIG. 12showing the syringe support structure in the syringe-disengagedposition;

[0061]FIG. 18 is a plan cross sectional view taken along thelongitudinal axis of the pressure jacket assembly of FIG. 12;

[0062]FIG. 19 is a cross sectional view taken along line 19-19 in FIG.18;

[0063]FIG. 20 is a perspective view of a spring device used in thesyringe support structure of the pressure jacket assembly of FIG. 12;

[0064]FIG. 21 is a perspective view of the syringe associated with thefluid injection apparatuses and pressure jacket assemblies of FIGS. 1and 12;

[0065]FIG. 22 is a perspective view of the syringe of FIG. 21 viewedfrom an opposite end;

[0066]FIG. 23 is a perspective view of a pressure jacket associated withthe pressure jacket assemblies of the present invention;

[0067]FIG. 24 is a cross sectional view taken along line 24-24 in FIG.23;

[0068]FIG. 25 is a cross sectional view taken along line 25-25 in FIG.23;

[0069]FIG. 26 is a cross sectional view taken along line 26-26 in FIG.23;

[0070]FIG. 27 is a plan cross sectional view taken along a longitudinalaxis of a prior art syringe;

[0071]FIG. 28 is a cross sectional view taken along line 28-28 in FIG.21;

[0072]FIG. 29 is a cross sectional view taken along line 29-29 in FIG.21;

[0073]FIG. 30 is a cross sectional view of another embodiment of thefluid injection apparatus and pressure jacket assembly of the presentinvention wherein the pressure jacket of the pressure jacket assemblycooperates directly with a faceplate of the fluid injection apparatus;and

[0074]FIG. 31 is cross sectional view of the pressure jacket assemblyand faceplate of FIG. 30 showing the position of the pressure jacketduring operation of the fluid injection apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0075]FIG. 1 shows a fluid injection apparatus 10 in accordance with thepresent invention. The fluid injection apparatus 10 includes an injectorhead 12, which may be supported on a support structure (not shown). Theinjector head 12 includes an injector housing 14 having a front end 16.A faceplate 18 is attached to the front end 16 of the injector housing14 and encloses the front end 16 of the injector housing 14. Thefaceplate 18 may be secured to the front end 16 of the injector housing14 by conventional means (i.e., mechanical fasteners and the like) or beintegrally formed with the injector housing 14.

[0076] Referring to FIGS. 1-4, the injector housing 14 has a centralopening 20 aligned with a central passage 21 defined by the faceplate 18and through which an injector drive piston 22 of the injector head 12 isextendable and retractable. The details of the injector head 12 and,more particularly, the injector drive piston 22 are described in U.S.Pat. No. 5,383,858, which was previously incorporated herein byreference. As described further herein, the injector head 12 isgenerally used to actuate a syringe 24 used in a fluid injectionprocedure, such as an angiographic procedure.

[0077] A pressure jacket assembly 30 is associated with the injectorhead 12. The pressure jacket assembly 30 supports the syringe 24 andmounts the syringe 24 to the injector head 12. Generally, the pressurejacket assembly 30 extends outward from the front end 16 of the injectorhousing 14 and is used to support the syringe 24 during the fluidinjection procedure. The pressure jacket assembly 30 is (generallycomprised by the faceplate 18, discussed previously, a cylindricalpressure jacket 32, a coupling member 34 for connecting the pressurejacket 32 to the faceplate 18, and a syringe support structure 36 forsupporting the syringe 24.

[0078] The pressure jacket 32 is a generally cylindrical structurehaving a front or distal end 42 and a rear or proximal end 44. Thedistal end 42 of the pressure jacket 32 defines a syringe receivingmouth or opening 45 for receiving the syringe 24 into the pressurejacket 32. The proximal end 44 of the pressure jacket 32 faces thefaceplate 18 and is configured to engage fixedly with the couplingmember 34. For this purpose, the proximal end 44 may have an externallythreaded portion 46. The pressure jacket 32 has an inner diameter sizedto smoothly but snugly receive the outer diameter of the syringe 24. Atypical clearance between the outer diameter of the syringe 24 and theinner diameter of the pressure jacket 32 may be about 0.005 inch. Thepressure jacket 32 is preferably made of a material capable ofrestraining the outward expansion of the syringe 24 during an injectionprocedure. As discussed previously, the syringe 24 by itself istypically not capable of withstanding the high pressures associated withcertain fluid injection procedures, such as angiography. The pressurejacket 32, as is well known in the art, is used to limit the radialexpansion of the syringe 24, which may lead to bursting or leaking, asdiscussed previously.

[0079] The syringe 24 may be made of a relatively inexpensive medicalgrade plastic material and may be disposable (i.e., single use).Alternatively, the syringe 24 may be a multi-patient use syringe.Typical plastics for the syringe 24 include polypropylene, polyethylene,and polycarbonate. The pressure jacket 32 is preferably reusable andmade of a material capable of withstanding pressures up to about 1200p.s.i. and higher. For example, the pressure jacket 32 may be made ofmetal such as steel or aluminum. However, as explained furtherhereinafter, it is advantageous for the syringe 24 to be visible throughthe pressure jacket 32 so that an operator of the fluid injectionapparatus 10 may view the syringe 24 during an injection procedure.Accordingly, the pressure jacket 32 is preferably made of asubstantially clear plastic material, such as polycarbonate, for viewingthe syringe 24 during an injection procedure.

[0080] The coupling member 34 is cylindrical shaped in a similar mannerto the pressure jacket 32. The coupling member 34 has a front or distalend 48 configured for connection to the pressure jacket 32 and a rear orproximal end 50 configured for connection to the faceplate 18. Thedistal end 48 includes internal threads forming an internally threadedportion 52. The threaded portion 46 at the proximal end 44 of thepressure jacket 32 cooperates with the internally threaded portion 52 ofthe coupling member 34 to secure the pressure jacket 32 to the couplingmember 34. The threaded connection between the pressure jacket 32 andcoupling member 34 is a presently preferred embodiment of the presentinvention and equivalent connections may be used in place of theabove-discussed threaded connection. Suitable equivalent connectionsinclude, but are not limited to: permanent bond, interference press fit,traditional mechanical fasteners, and the like. The coupling member 34may be made of any of the materials discussed previously in connectionwith the pressure jacket 32. In an alternative embodiment, the couplingmember 34 may be eliminated and the pressure jacket 32 connecteddirectly to the faceplate 18, an example of which is shown in FIGS. 30and 31 discussed hereinafter.

[0081] Referring to FIGS. 1-6, the coupling member 34 is removablyconnected to the faceplate 18 attached to the front end 16 of theinjector housing 14. A presently preferred embodiment of the presentinvention provides a bayonet socket connection between the couplingmember 34 and the faceplate 18. In particular, for this purpose, theproximal end 50 of the coupling member 34 includes a pair of oppositelyfacing bayonet projections 54, 56. The bayonet projections 54, 56 arepositioned to cooperate with a flange 58 extending outward from thefaceplate 18. The flange 58 defines a pair of opposing recesses 60, 62for receiving the bayonet projections 54, 56 into the flange 58. Theflange 58 further defines a pair of bayonet receiving slots 64, 66. Thebayonet projections 54, 56 may be inserted into the flange 58 throughthe recesses 60, 62 and then rotated to engage the bayonet receivingslots 64, 66 to secure the coupling member 34 to the faceplate 18. Thebayonet receiving slots 64, 66 may be formed so that, for example, aone-quarter turn of the coupling member 34 after being inserted into therecesses 60, 62 will secure the coupling member 34 to the faceplate 18.

[0082] The bayonet receiving slots 64, 66 are preferably configured suchthat when the bayonet projections 54, 56 are received in the bayonetreceiving slots 64, 66 and the threaded portion 46 of the proximal end44 of the pressure jacket 32 is threaded into the threaded portion 52 ofthe coupling member 34, the bayonet projections 54, 56 fully seat in thebayonet receiving slots 64, 66. Accordingly, the engagement of thebayonet projections 54, 56 in the bayonet receiving slots 64, 66facilitates threading of the proximal end 44 of the pressure jacket 32into the distal end 48 of the coupling member 34. The threadedconnection between the pressure jacket 32 and coupling member 34 may beconventional (i.e., clockwise rotation for engagement, counterclockwiserotation for disengagement). However, the conventional arrangement maybe reversed in accordance with the present invention. Additionally, thebayonet socket connection between the coupling member 34 and thefaceplate 18 may be replaced by any suitably equivalent mechanicalconnection, such as by a threaded connection, magnets, traditionalmechanical fasteners, snap ring, and the like.

[0083] The syringe 24 used in the fluid injector apparatus 10 generallyincludes an elongated, cylindrical syringe body 70 having a front ordistal end 72 and a rear or proximal end 74. The syringe body 70 has aninjection section 76 formed at the distal end 72. As discussed furtherherein, the syringe body 70 preferably includes an expansion section 78at the proximal end 74. A generally cylindrical center section or mainbody 80 of the syringe body 70 connects the injection section 76 and theexpansion section 78. The center section (i.e., main body) 80 has arelatively uniform outer diameter. The injection section 76 tapers toform an elongated injection neck 82, which has a relatively small innerdiameter compared to the inner diameter of the center section 80. Theinjection section 76 and injection neck 82 generally form the dischargeoutlet of the syringe 24. The syringe support structure 36 is configuredto support the injection section 76 of the syringe body 70.

[0084] The syringe support structure 36 includes at least one, andpreferably two, support arms 90, 92 extending outward from the injectorhousing 14. In particular, the support arms 90, 92 extend throughrespective front openings 94, 96 defined in the faceplate 18 attached tothe injector housing 14. The front openings 94, 96 in the faceplate 18are substantially vertically oriented to allow the support arms 90, 92to pivot up and down with respect to the injector housing 14. Thesupport arms 90, 92 have rear or proximal ends 98, 100, respectively,extending into the injector housing 14, and distal ends 102, 104,respectively, projecting outward from the injector housing 14. Thedistal ends 102, 104 of the support arms 90, 92 are interconnected by asyringe retaining wall or member 106. The syringe retaining member 106may be affixed to the support arms 90, 92 by conventional mechanicalfasteners (i.e., bolts) and the like. The syringe retaining member 106defines a central syringe receiving slot 108 that is substantiallyvertically oriented and is configured to receive and support theinjection neck 82 of the injection section 76. The syringe retainingmember 106 further defines one or more openings 110, which are spacedradially outward from the syringe receiving slot 108. The syringereceiving slot 108 and openings 110 permit the operator of the fluidinjection apparatus 10 to view the syringe 24 during an injectionprocedure. More importantly, the syringe receiving slot 108 and openings110 permit the operator to view the injection section 76 during aninjection procedure.

[0085] Referring to FIGS. 1-11, as stated, the proximal ends 98, 100 ofthe support arms 90, 92 extend into the injector housing 14. The supportarms 90, 92 are generally configured to be movable between a firstposition (FIG. 7) wherein the syringe retaining member 106 receives theinjection neck 82 and cooperates with the injection section 76 of thesyringe body 70 and prevents removal of the syringe 24 from the pressurejacket 32, and a second, rotated position (FIG. 8) wherein the injectionneck 82 and the injection section 76 of the syringe body 70 aredisengaged sufficiently from the syringe receiving slot 108 and syringeretaining member 106 to allow removal of the syringe 24 from thepressure jacket 32. In particular, in the second position, the injectionneck 82 is disengaged sufficiently from the syringe receiving slot 108and the injection section 76 is sufficiently decoupled from the syringeretaining member 106 to allow the syringe 24 to be removed easily fromthe front loading pressure jacket 32. Preferably, in the secondposition, the support arms 90, 92 and syringe retaining member 106 arespaced a distance below the pressure jacket 32 and syringe 24. With thesupport arms 90, 92 in the first position, the syringe support structure36 is in a syringe-engaged position. When the support arms 90, 92 aremoved to the second position, the syringe support structure 36 isgenerally in a syringe-disengaged or removal position or configuration.

[0086] The support arms 90, 92 generally follow a two-dimensional (i.e.,X and Y) movement in their motion between the first and secondpositions. In particular, the support arms 90, 92 are configured to movefrom the first (i.e., syringe-engaged) position to the second (i.e.,syringe-removal) position by generally moving distally or linearlyforward away from the faceplate 18 and then generally rotate downwardfrom the pressure jacket 32 and syringe 24. Similarly, the support arms90, 92 are configured to return to the first position by rotating upwardtoward the pressure jacket 32 and syringe 24 and then moving proximallytoward the faceplate 18 so that the injection neck 82 is again receivedin the syringe receiving slot 108 and the retaining member 106cooperates with the injection section 76 to secure the syringe 24.

[0087] An axle assembly 112 interconnects the proximal ends 98, 100 ofthe support arms 90, 92 and facilitates the two-dimensional movementexhibited by the support arms 90, 92 generally described hereinabove.The axle assembly 112 is located within the injector housing 14 and isconnected to an internal facing side 114 of the faceplate 18. The axleassembly 112 is comprised generally of an axle linkage 116, a pair ofcircular-shaped members 118, 120, a pair of support brackets 122, 124,and an actuation handle 126.

[0088] The axle linkage 116 is comprised of a U-shaped base member 128having two outward extending axles 130, 132, one for each of the supportarms 90, 92. The base member 128 defines an opening or recess 134through which the injector drive piston 22 of the injector head 12 mayextend and retract to actuate a syringe plunger located in the syringe24 as discussed further herein. The axles 130, 132 each include apolygonal shaped portion 136 for engaging the circular members 118, 120.

[0089] The proximal ends 98, 100 of the support arms 90, 92 definerespective circular apertures 138, 140, which are configured to receivethe circular members 118, 120, respectively. The circular members 118,120 are seated for rotation in the circular apertures 138, 140. Thecircular members 118, 120 define polygonal shaped openings 142, 144,respectively, to receive the polygonal shaped portions 136 of the axles130, 132. At least one of the axles 130, 132, in this case axle 130, isconfigured to support the actuation handle 126. For this purpose, axle130 extends outward from the injector housing 14. The actuation handle126 is seated over the end of the axle 130 and is preferably securedfixedly to the end of the axle 130 so that rotational motion imparted tothe actuation handle 126 is transmitted to the axles 130, 132. Bushings146, 148 may be provided on the axles 130, 132 to facilitate therotational movement of the axles 130, 132 with respect to the supportbrackets 122, 124.

[0090] In the assembled axle assembly. 112, the proximal ends 98, 100 ofthe support arms 90, 92 are received in recesses 150, 152 defined by thesupport brackets 122, 124, respectively. The support brackets 122, 124are generally U-shaped in horizontal cross section and each have twosidewalls 154, 156 interconnected by an end wall 158. The sidewalls 154,156 of each of the support brackets 122, 124 define aligned openings160, 162. The sidewalls 154, 156 and end walls 158 of the brackets 122,124 form the respective recesses 150, 152. The axles 130, 132 extendthrough the aligned openings 160, 162 in the support brackets 122, 124to interconnect the proximal ends 98, 100 of the support arms 90, 92.

[0091] The U-shaped base member 128 of the axle linkage 116 is locatedbetween the support brackets 122, 124 with the opening 134 defined bythe base member 128 aligned with the central passage 21 in the faceplate18 to permit the injector drive piston 22 to extend outward from andretract into the injector housing 14. The support brackets 122, 124 aresecured fixedly to the internal facing side 114 of the faceplate 18 tosupport the axle assembly 112. The support brackets 122, 124 may besecured to the internal facing side 114 of the faceplate 18 byconventional mechanical fasteners 164 (i.e., bolts) and the like. Theopening 134 defined by the base member 128 is formed to permit theinjector drive piston 22 to extend or retract regardless of the positionof the syringe support structure 36 (i.e., syringe-engaged or removalpositions). The base member 128 is generally square or rectangularshaped and the opening 134 is formed by two substantiallysemi-circular-shaped passages formed into the rectangular-shaped basemember 128.

[0092] The circular members 118, 120 facilitate the two-dimensionalmovement exhibited by the support arms 90, 92 identified previously. Asstated previously, the support arms 90, 92 are generally movable from afirst (i.e., syringe-engaged) position to a second (i.e.,syringe-removal) position by first moving distally away from thefaceplate 18 and then downward to the second position depending belowthe pressure jacket 32 and syringe 24. The circular members 118, 120 arecams that enable the axial or distal movement of the support arms 90,92. The circular members 118, 120 also provide for the rotational orpivotal movement of the support arms 90, 92 to the second positiondepending below the pressure jacket 32 and syringe 24, which allows thesyringe 24 to be removed from the pressure jacket 32. The distal oraxial movement of the support arms 90, 92 is important because itpermits the syringe retaining member 106 to disengage from the injectionsection 76 of the syringe body 70 and to clear the distal end 42 of thepressure jacket 32 when the support arms 90, 92 are rotated to thesecond position depending below the pressure jacket 32 and syringe 24.

[0093] As indicated previously, the circular members 118, 120 rotate ontheir respective axles 130, 132 when the handle 126 is actuated. Theopenings 142, 144, through which the respective axles 130, 132 extend,are offset from the center of the circular members 118, 120. Thus, thecenter of the circular members 118, 120 is a distance away from therotational axis of the circular members 118, 120 (i.e., axles 130, 132).This distance is the “throw” of the “camming” circular members 118, 120and is the axial distance that the support arms 90, 92 move distally orlinearly away from the faceplate 18 under the camming action of thecircular members 118, 120. This axial distance, as indicated previously,permits the syringe retaining member 106 to dissengage from theinjection section 76 of the syringe body 70 and clear the distal end 42of the pressure jacket 32 when the support arms 90, 92 are pivoted tothe second position.

[0094] Referring, in particular, to FIGS. 9-11, one of the circularmembers 118, 120, (i.e., circular member 120) and one of the supportarms 90, 92 (i.e., support arm 92) are shown. FIG. 9 shows the circularmember 120 in a “closed” position, which corresponds generally to thesupport arms 90, 92 and syringe retaining member 106 being in the firstor syringe-engaged position. FIG. 10 shows the circular member 120 in an“open” position, which corresponds generally with the support arms 90,92 and syringe retaining member 106 being in an intermediate positionmoved distally forward from the faceplate 18, or in the second,syringe-removal position. FIG. 11 shows the orientation of support arm92 after being moved fully to the second position. The support arm 90follows an identical movement to the support arm 92.

[0095] As stated, in the closed position of the circular members 118,120, the support arms 90, 92 and syringe retaining member 106 are in thefirst, syringe-engaged position, wherein the syringe retaining member106 engages the injection section 76 of the syringe body 70. To move thesupport arms 90, 92 and syringe retaining member 106 to the second,syringe-removal position, the handle 126 is rotated, for example, in aclockwise direction. This clockwise movement causes the circular members118, 120 to rotate with their respective axles 130, 132. The supportarms 90, 92 and syringe retaining member 106 move distally or linearlyforward by the camming action of the circular members 118, 120 to theintermediate position. The intermediate position of the support arms 90,92 and syringe retaining member 106 corresponds generally to the fullyrotated “open” position of the circular members 118, 120 shown in FIGS.10 and 11. Once the support arms 90, 92 and the syringe retaining member106 are in the intermediate position, they may be rotated or pivotedfully to the second position. The support members 90, 92 are moved tothe second position by simply exerting downward pressure on the supportarms 90, 92. The support arms 90, 92 and syringe retaining member 106rotate about the circular members 118, 120 to move to the secondposition depending below the pressure jacket 32 and syringe 24,preferably sufficiently downward to permit the syringe 24 to be removedeasily from the front loading pressure jacket 32. Thus, the actuationhandle 126 is used primarily to “open” the camming circular members 118,120 and move the support arms 90, 92 and syringe retaining member 106 tothe intermediate position. Thereafter, the operator provides the motiveforces to move the syringe support structure 36 out of the way for asyringe-removal operation.

[0096] The rotational movement of the circular members 118, 120 in thecircular apertures 138, 140 is preferably limited. For this purpose, thecircular members 118, 120 define respective slots 166, 168, which extendthrough the circular members 118, 120. The slots 166, 168 are generallyarcuate shaped, and preferably define an arc of a circle. The sidewallsof the 154, 156 of the respective support brackets 122, 124 each definea pin receiving opening 170. A pair of pins 172, 174 extends through thepin receiving openings 170 in the respective brackets 122, 124 and theslots 166, 168 in the respective circular members 118, 120. The pins172, 174 cooperating with the pin receiving openings 170 and slots 166,168 limit the rotational movement of the circular members 118, 120 inthe circular apertures 138, 140 to approximately a one-quarter turn(i.e., one-quarter rotation) in the circular apertures 138, 140. Theslots 166, 168 prevent the circular members 118, 120 from beingover-rotated by providing hard stops, which limit the rotationalmovement of the circular members 118, 120. Preferably, the hard stopscorrespond to the open and closed positions of the circular members 118,120. Thus, one hard stop generally corresponds to the support arms 90,92 and syringe receiving member 106 being in the first orsyringe-engaged position and the circular members 118, 120 being in theclosed position. The second hard stop is located at the end of the axialmovement of the support arms 90, 92 (i.e., intermediate position). Theslots 166, 168 generally operate as guide tracks that guide and limitthe rotational movement of the “camming” circular members 118, 120.

[0097] The proximal ends 98, 100 of the support arms 90, 92 preferablydefine respective guide tracks 176, 178, which guide the movement of thesupport arms 90, 92 as they move distally or linearly away from thefaceplate 18 under the influence of the circular members 118, 120. Theguide tracks 176, 178 define the exact path for the support arms 90, 92to follow in their movement from the first or syringe-engaged positionto the intermediate position. The guide tracks 176, 178 also define andlimit the movement of support arms 90, 92 when they are pivoted fully tothe second or syringe-removal position. A pair of cross pins 180, 182cooperates with the guide tracks 176, 178 respectively. The cross pins180, 182 extend through the faceplate 18 to cooperate with the guidetracks 176, 178, respectively. The cross pins 180, 182 are preferablyfixed to the faceplate 18.

[0098] The path defined by the guide tracks 176, 178 generally causesthe support arms 90, 92 and syringe retaining member 106 to movedistally or linearly away from the faceplate 18 and slightly verticallydownward from the first position (FIG. 9) to the intermediate position(FIG. 10). To move the support arms 90, 92 and the syringe retainingmember 106 fully to the second position, the operator of the fluidinjection apparatus 10 exerts downward force on the support arms 90, 92.The cross pins 180, 182 and guide tracks 176, 178 act as a guiding andstopping mechanism to prevent the support arms 90, 92 from impingingdownward onto the faceplate 18 in the vertical front openings 94, 96. Asshown in FIG. 11, the cross pins 180, 182 seat in the upper ends of theguide tracks 176, 178 during the downward movement of the supportmembers 90, 92, which restricts the downward movement of the supportarms 90, 92 to a specific distance.

[0099] Preferably, the support arms 90, 92 further define detentopenings or recesses 184, 186, respectively, located generally below andoffset from the guide tracks 176, 178. The detent openings 184, 186cooperate with a pair of ball detents 188, 190 attached to the faceplate18. The ball detents 188, 190 are generally located below the cross pins180, 182 and are secured to the faceplate 18. The ball detents 188, 190mate with the detent openings or recesses 184, 186 when the support arms90, 92 and syringe retaining member 106 are moved to the intermediateposition. The mating connection between the ball detents 188, 190 anddetent openings 184, 186 operates to hold the support arms 90, 92 in theintermediate position prior to exerting downward force on the supportarms 90, 92 to move the support arms 90, 92 fully to the secondposition. The ball detents 188, 190 also provide a tactile andpreferably audible indication that the support arms 90, 92 are correctlyset in the intermediate position and the circular members 118, 120 areset in the open position.

[0100] The mating connection between the ball detents 188, 190 anddetent openings 184, 186 allows one-handed operation of the fluidinjection apparatus 10. For example, during a syringe loading operation,once the syringe 24 is loaded in the pressure jacket 32, the supportarms 90, 92 may be rotated upward with one hand until the ball detents188, 190 mate with the detent openings 184, 186, which will support thesupport arms 90, 92 until the circular members 118, 120 are rotated tothe closed position by the actuation handle 126 and the support arms 90,92 and syringe retaining member 106 are moved distally back to the firstor syringe-engaged position.

[0101] The circular members 118, 120 define respective ball detentreceiving openings 192, 194 having a second ball detent 196 locatedtherein. The ball detents 196 cooperate with ball detent openings orrecesses 198 defined in the sidewalls 154, 156 of the brackets 122, 124when the circular members 118, 120 are in the closed position (FIG. 9).The mating connection between the ball detents 196 and detent openings198 provides a tactile and preferably audible indication that thecircular members 118, 120 are in the closed position and, further, thatthe support arms 90, 92 and syringe receiving member 106 are set in thefirst or syringe-engaged position. These tactile and auditory cuesenable the operator of the fluid injection apparatus 10 to recognizewhen the support members 90, 92 and syringe retaining member 106 are inthe correct position to begin a fluid injection procedure.

[0102] Referring to FIGS. 12-20, a second embodiment of the fluidinjection apparatus 10′ and the pressure jacket assembly 30′ of thepresent invention are shown. In FIGS. 12-20, the injector head 12′ andinjector housing 14′ are omitted to simplify explanation of the fluidinjection apparatus 10′, but these elements should be considered to bepart of the fluid injection apparatus 10′. The coupling member 34′ andfaceplate 18′ of the pressure jacket assembly 30′ cooperate in the samemanner as the coupling member 34 and faceplate 18 discussed previously.The faceplate 18′ is substantially identical to the faceplate 18discussed previously, with the exception that the support arms 90′, 92′are now pivotally connected directly to the faceplate 18′, rather thaninterconnected in the injector housing 14′ and supported on the internalfacing side 114′ of the faceplate 18′. For this purpose, the circularapertures 138′, 140′ in the proximal ends 98′, 100′ of the support arms90′, 92′ are made smaller and aligned with side openings 200, 202defined in the sides of the faceplate 18′, respectively. The proximalends 98′, 100′ of the support arms 90′, 92′ are pivotally connected tothe faceplate 18′ by pivotal connections 203 (i.e., mechanicalfasteners, such as bolts and the like). The pivotal connections 203between the proximal ends 98′, 100′ of the support arms 90′, 92′ and thefaceplate 18′ allow the support arms 90′, 92′ to move between the firstand second positions described previously. However, the movementexhibited by the support arms 90′, 92′ between the first and secondpositions in the fluid injection apparatus 10′ is now substantiallypivotal or rotational motion rather than the translational androtational movement described previously.

[0103] The pressure jacket 32′ and coupling member 34′ cooperate in thesame manner as described previously in connection with the first fluidinjection apparatus 10. However, the pressure jacket 32′ is slightlymodified in comparison with the pressure jacket 32 discussed previously.The distal end 42′ of the pressure jacket 32′ now defines a beveledportion 204. The beveled portion 204 generally comprises approximatelyhalf of the circumference of the distal end 42′ of the pressure jacket32′. As shown, for example, in FIG. 15, the beveled portion 204 definesan acute angle θ with a central axis L of the pressure jacket 32′. Thebeveled portion 204 preferably defines an acute angle of between about5° and 60° with the central axis L of the pressure jacket 32′. It ispreferred that the beveled portion 204 defines an angle θ less thanabout 60°. In general, the beveled portion 204 allows the syringeretaining member 106′ to pivot or rotate between a syringe-retainingposition wherein the syringe retaining member 106′ prevents removal ofthe syringe 24 from the pressure jacket 32′, and a pivoted positionwherein an upper portion of the syringe retaining member 106′ is spacedfrom the injection section 76 of the syringe 24, which allows thesupport arms 90′, 92′ and the syringe retaining member 106′ to berotated downward to the second or syringe-removal position, as discussedpreviously. The beveled portion 204 generally provides the axialdistance necessary for the syringe retaining member 106′ to disengagefrom the injection section 76 of the syringe 24 and clear the distal end42′ of the pressure jacket 32′ when the support arms 90′, 92′ andsyringe retaining member 106′ are to be rotated downward from thepressure jacket 32.

[0104] The threaded connection between the externally threaded portion46′ at the proximal end 44′ of the pressure jacket 32′ and theinternally threaded portion 52′ of the coupling member 34′ is preferablyconfigured such that when the proximal end 44′ is fully threaded intothe internally threaded portion 52′, the beveled portion 204 forms thelower part of the pressure jacket 32′ (i.e., lies below a horizontalplane generally bisecting the cylindrical shaped pressure jacket 32′when the pressure jacket 32′ is mounted to the faceplate 18′). Thepressure jacket 32′ is configured to receive the syringe 24 in the samefront-loading manner as the pressure jacket 32 discussed previously.

[0105] The syringe retaining member 106′ differs from the syringeretaining member 106 discussed previously in that the syringe retainingmember 106′ is pivotally connected by pivotal connections 205 (i.e.,mechanical fasteners and the like) to the distal ends 102′, 104′ of thesupport arms 90′, 92′. The pivotal connections 205 permit the upperportion of the syringe retaining member 106′ to pivot away from theinjection section 76 of the syringe body 70, and the lower portion topivot toward the beveled portion 204. As indicated previously, thispivotal movement generally enables the syringe retaining member 106′ todisengage from the injection section 76 of the syringe body 70 (i.e.,syringe-retaining position). The beveled portion 204 correspondinglyprovides the necessary clearance for the syringe retaining member 106′to pass over the distal end 42′ of the pressure jacket 32′ when thesupport arms 90′, 92′ and syringe retaining member 106′ are to be movedfrom the first to the second positions and vice versa.

[0106] As shown, for example, in FIGS. 13 and 19, the syringe retainingmember 106′ has a syringe facing side 206 that is generally formed tocooperate with the conical shape of the injection section 76 of thesyringe body 70. The syringe facing side 206 of the syringe retainingmember 106′ defines respective cavities 207, 208 adjacent the distalends 102′, 104′ of the support arms 90′, 92′. The cavities 207, 208house respective springs 209 (i.e., spring means), such as leaf springs.The springs 209 are positioned to act between the distal ends 102′, 104′of the support arms 90′, 92′ and the syringe retaining member 106′. Inparticular, the springs 209 are adapted to bias the syringe retainingmember 106′ to a position oriented substantially perpendicular to thelongitudinal axes of the support arms 102′, 104′. For example, when thesyringe retaining member 106′ is pivoted toward the beveled portion 204(i.e., pivoted postion), the springs 209 provide a counter-acting forcethat acts to bias the syringe retaining member 106′ back to asubstantially 90° position with respect to the support arms 90′, 92′.The springs 209 may be replaced by any equivalent spring device such asa compression coil spring and the like.

[0107] In summary, the spring-biased syringe retaining member 106′ ismovable between a first or syringe-retaining position wherein thesyringe retaining member 106′ cooperates with the injection section 76and prevents removal of the syringe 24 from the pressure jacket 32′, anda second, pivoted position wherein the syringe facing side 206 of thesyringe retaining member 106′ disengages from the injection section 76of the syringe 24 thereby permitting the syringe retaining member 106′and support arms 90, 92 to be moved to the second or syringe-removalposition to allow removal of the syringe 24 from the pressure jacket32′.

[0108] The support arms 90′, 92′ are preferably formed to create amoment that will maintain the support arms 90′, 92′ and syringeretaining member 106′ in the first or syringe-engaged position. In thefirst position, the support arms 90′, 92′ are oriented substantiallyparallel to the syringe 24. As shown, for example, in FIG. 15, thesupport arm 90′ reduces in cross section at the distal end 102′ of thesupport arm 90′ and increases in cross section at the proximal end 98′.In particular, a portion 210 of the support arm 90′ proximate to thedistal end 102′ of support arm 90′ has a reduced cross sectional areaand, hence, has a reduced mass, and a portion 211 of the support arm 90′proximate to the distal end 102′ of the support arm 90′ has an increasedcross sectional area and has increased mass. The mass differencesbetween the distal end 102′ and proximal end 98′ of the of the supportarm 90′ creates a moment about the pivotal connection 203 with thefaceplate 18′. The other support arm 92′ has a similar reduced crosssectional portion 210 at its distal end 104′. The moments created by thesupport arms 90′, 92′ maintain the support arms 90′, 92′ orientedsubstantially parallel to the pressure jacket 32′ and syringe 24, whichmaintains the syringe retaining member 106′ in the syringe retainingposition generally in engagement with the syringe 24.

[0109] Additional features of the syringe 24 associated with the fluidinjection apparatuses 10, 10′ will now be discussed with reference toFIGS. 2-4, 21 and 22. As stated previously, the syringe 24 may be asingle-use syringe or a multi-patient use syringe. The injection section76 of the syringe body 70 generally tapers inward toward a central axisL of the syringe body 70. The injection section 76 includes a conicalportion 212 tapering from the cylindrical shaped center section or mainbody 80 to the injection neck 82. The conical portion 212 defines analignment flange or tab member 214. This alignment flange or tab member214, in a preferred embodiment, defines a hollow space or area therein.The alignment flange or tab member 214 is provided as a means to viewthe fluid within the syringe 24. Additionally, the alignment flange ortab member 214 acts as a visual indicator for properly aligning thesyringe 24 in the pressure jacket(s) 32, 32′. Further, the alignmentflange or tab member 214 provides a convenient handle for manipulatingthe syringe 24 and inserting it into the pressure jacket(s) 32, 32′.Secondarily, the hollow space defined by the alignment flange 214 mayoperate as an air bubble trap. Preferably, the alignment flange or tabmember 214 generally extends the distance between the center section 80of the syringe body 70 and the injection neck 82. A fluid dot, such as aglow-in-the-dark fluid dot 215 may be formed in the conical portion 212as an optical aid.

[0110] The syringe plunger 216 is configured for connection to theinjector drive piston 22. As mentioned previously, the injector drivepiston 22 is extendable through the central passage 21 in the faceplate18 for imparting motive forces to a syringe plunger disposed within thesyringe 24. Accordingly, the injector drive piston 22 is preferablymotorized. The injector drive piston 22 includes a rectangular injectorend plate 218, which is adapted to capture the syringe plunger 216 andimpart motion to the syringe plunger 216. The end plate 218 may includean integral, axially located light source 219 to illuminate the fluidloaded into the syringe 24. The syringe plunger 216 is generallyconical-shaped to cooperate with the conical portion 212 of theinjection section 76 of the syringe body 70. The syringe plunger 216includes a base member 220 that is substantially enclosed by a cover222, which forms the conical shape of the syringe plunger 216 and may bemade of rubber, for example. The syringe plunger 216 includes a couplingend 224 that faces the proximal end 74 of the syringe body 70. Thesyringe plunger 216 may be transparent to allow light from the lightedinjector end plate 218 to pass therethrough. In a preferred embodiment,a pair of flexible lug or coupling members 226 extend outward from thecoupling end 224 for engaging the injector drive piston 22 and, moreparticularly, the injector end plate 218 attached to the injector drivepiston 22, as described in U.S. Pat. Nos. 5,873,861 and 5,947,935, thedisclosures of which are incorporated herein by reference. The couplingmembers 226 are flexible and may be integrally formed with the basemember 220. In an alternative embodiment, the coupling members may besubstantially fixed or rigid, as described in U.S. Pat. No. 4,677,980,which was previously incorporated by reference into this disclosure. Thecoupling members 226 each have an engagement arm 228. The couplingmembers 226 define a slot 230 therebetween. The slot 230 is configuredto receive the injector end plate 218 attached to the injector drivepiston 22. The alignment flange or tab member 214 provides a last resortair containment feature when the distal end (i.e., cover 222) extendsinto and “bottoms-out” in the conical portion 212. Any unnoticed airbubbles will tend to collect in the hollow area defined by the alignmentflange or tab member 214 during operation of the injector head 12.

[0111] To facilitate aligning the slot 230 with the rectangular injectorend plate 218 of the injector drive piston 22, the slot 230 ispreferably aligned with the alignment flange or tab member 214, so thatthe alignment flange or tab member 214 provides a visual indication ofthe orientation of the slot 230. Thus, the operator of the fluidinjection apparatus(es) 10, 10′ will have a visual indication of thelocation of the slot 230 while inserting the syringe 24 into thepressure jacket(s) 32, 32′ and attempting to place the syringe plunger216 in engagement with the injector drive piston 22. The alignmentflange 214 automatically orients the coupling members 226 in a desiredmounting position aligned with the rectangular injector end plate 218when the syringe 24 is inserted into the pressure jacket(s) 32, 32′. Thealignment flange 214 preferably extends sufficiently outward from theconical portion 212 to be grasped by the operator of the fluid injectionapparatus(es) 10, 10′ and used as a handle for manipulating the syringe24, particularly during loading the syringe 24 into the pressurejacket(s) 32, 32′. The alignment flange 214 and syringe plunger 216 arepreferably oriented so that the alignment flange 214 is orientedsubstantially vertically when the syringe 24 is loaded into the pressurejacket(s) 32, 32′. Thus, in this “loaded position”, the slot 230 is alsovertically oriented to engage the injector end plate 218. Additionally,in the preferred loaded position of the syringe 24, the air viewingfeature of the alignment flange 214 is maximized.

[0112] To load the syringe 24 in the pressure jacket assembly 30 asshown in FIGS. 1-11, the following procedure is generally followed. Thesupport arms 90, 92 and syringe retaining member 106 are located in thesecond or syringe removal position depending downward from the pressurejacket 32. The distal end 42 of the pressure jacket 32 is therebyexposed permitting the syringe 24 to be inserted into the syringereceiving opening 45. The syringe 24 is front loaded into the pressurejacket 32 with the alignment flange 214 substantially aligned tovertical. This aligns the coupling members 226 of the syringe plunger216 in the desired mounting position in which the slot 230 is alignedvertically with the rectangular injector end plate 218 attached to theinjector drive piston 22. Once the syringe 24 is properly seated in thepressure jacket 32, the operator rotates the support arms 90, 92 (andsyringe retaining member 106) upward to the intermediate position. Theoperator then rotates the actuation handle 126 counter-clockwise, forexample, to move the support arms 90, 92 (and syringe retaining member106) proximally toward the faceplate 18 and back to the firstsyringe-engaged position, wherein the syringe retaining member 106engages the conical portion 212 of the syringe 24. The injection neck 82of the syringe body 70 is received in the syringe receiving slot 108defined in the retaining member 106. The alignment flange 214 ispreferably aligned with the syringe receiving slot 108, which aligns thecoupling members 226 to engage the injector end plate 218. The syringe24 may then be placed in fluid communication with the fluid that is tobe injected into the patient. Once the syringe 24 is filled with thedesired fluid, the operator may view the fluid in the injection section76 of the syringe body 70 through the openings 110 in the retainingmember 106 and through the syringe receiving slot 108 to ensure that airis not present in the syringe 24.

[0113] Once the fluid injection apparatus 10 is placed in fluidcommunication with the body of a patient, the operator may actuate theinjector drive piston 22. As the injector drive piston 22 moves forwardthrough the central passage 21 in the faceplate 18, the injector endplate 218 contacts the engagement arms 228 of the coupling members 226.As the injector drive piston 22 continues to move forward, the injectorend plate 218 urges the flexible coupling members apart until theinjector end plate 218 is seated in the vertical slot 230 between thecoupling members 226. The injector drive piston 22 may then apply motiveforces to the syringe plunger 216 to inject the fluid into the patient.The engagement arms 228 secure the engagement between the injector drivepiston 22 and the syringe plunger 216 during the procedure and permitthe plunger 216 to be withdrawn (i.e., moved proximally at the end ofthe procedure, if necessary). The fluid in the syringe 24 may beilluminated by the light source integrated into the injector end plate218.

[0114] Once the fluid injection procedure is complete, the operator ofthe fluid injection apparatus 10 rotates the actuation handle 126clockwise, which moves the support arms 90, 92 and syringe retainingmember 106 to the intermediate position. In the intermediate position,the syringe retaining member 106 is partially disengaged from theconical portion 212 of the syringe 24. The operator then appliesdownward force on the support arms 90, 92 to move the support arms 90,92 and syringe retaining member 106 to a position depending below thepressure jacket 32 and syringe 24 (i.e., second or syringe-removalposition). The syringe 24 may then be removed from the pressure jacket32, once the injector end plate 218 is disengaged from the syringeplunger 216.

[0115] The fluid injection apparatus 10′ operates in a substantiallyanalogous manner to the fluid injection apparatus 10 discussedhereinabove. The operation of the fluid injection application 10′differs from the fluid injection apparatus 10 in that the syringeretaining member 106′ pivots with respect to the support arms 90′, 92′and the support arms 90′, 92′ pivot with respect to the injector housing14 and faceplate 18 without moving axially toward or away from theinjector housing 14 and faceplate 18. The general operation of the fluidinjection apparatus 10′ will be discussed with reference to FIGS. 12-20.

[0116] With the support arms 90′, 92′ in the first position and thesyringe retaining member 106′ in the syringe-retaining position, thesyringe retaining member 106′ supports the injection neck 82 andprevents removal of the syringe 24 from the pressure jacket 32′. Thesprings 209 maintain the syringe retaining member 106′ in thesyringe-retaining position oriented substantially perpendicular to thesupport arms 90′, 92′. During an injection procedure, the syringe 24will generally move distally forward, contact, and exert force on thesyringe facing side 206 of the syringe retaining member 106′. Thesyringe facing side 206 is generally formed to cooperate with theconical portion 212 of the syringe 24. The moments provided by thenon-continuous cross section support arms 90′, 92′ are generallysufficient to maintain the support arms 90′, 92′ and the syringeretaining member 106′ in the first or syringe-engaged position andprevent the syringe retaining member 106′ from pivoting with respect tothe support arms 90′, 92′ about the pivotal connections 205.

[0117] After an injection procedure is completed, the syringe 24 may beremoved from the pressure jacket 32′. This is accomplished by theoperator of the fluid injection apparatus 10′ grasping the syringeretaining member 106′ and pivoting the syringe retaining member 106′from the syringe retaining position to the pivoted position, as shownfor example in FIG. 13. The syringe retaining member 106′ rotates aboutthe pivotal connections 205 so that the upper portion of the syringefacing side 206 of the syringe retaining member 106′ disengages from theinjection section 76 of the syringe body 70 and the lower portion of thesyringe facing side 206 rotates or pivots toward the beveled portion 204of the pressure jacket 32′. With the syringe retaining member 106′ nowdisengaged substantially from the syringe 24, the syringe retainingmember 106′ and support arms 90′, 92′ may be rotated to a positiondepending downward from the pressure jacket 32′ by the operator (i.e.second or syringe-removal position). In this movement, the support arms90′, 92′ pivot about the pivotal connections 203 connecting the proximalends 98′, 100′ of the support arms 90′, 92′ to the faceplate 18′. Thebeveled portion 204 provides the necessary clearance for the syringeretaining member 106′ to clear the distal end 42′ of the pressure jacket32′. The used syringe 24 may be removed and replaced with a new syringe24 for the next injection process. The foregoing process may be reversedto return the syringe retaining member 106′ and the support arms 90′,92′ to the correct position for another procedure. The support members90′, 92′ will automatically orient to the first or syringe-engagedposition by the moments created by the non-continuous cross sectionalportions 210′, 211′ of the support arms 90′, 92′, as discussedpreviously, which will place the syringe retaining member 106′ in thecorrect position to cooperate with the conical portion 212 of thesyringe 24. The springs 209 will automatically orient the syringeretaining member 106′ with respect to the support arms 90′, 92′ andsyringe 24 when the support arms 90′, 92′ are returned to the first orsyringe-engaged position.

[0118] FIGS. 5-8 show additional features of the fluid injectionapparatuses 10, 10′ of the present invention. The following discussionis made with reference to the first embodiment of the fluid injectionapparatus 10, but is equally applicable to the second embodiment of thefluid injection apparatus 10′ and (pressure jacket assembly 30′)discussed previously. During the fluid injection procedure, it isespecially advantageous for the operator of the fluid injectionapparatus 10 to view the fluid contents of the syringe 24. Of particularimportance is the ability of the operator to view the fluid within thesyringe 24. Accordingly, the present fluid injection apparatus 10includes an illumination feature for illuminating the syringe 24 duringa fluid injection procedure.

[0119] As shown in FIGS. 5-8, the pressure jacket assembly 30 furtherincludes at least one light source 240 attached to one or both of thesupport arms 90, 92 and facing the pressure jacket 32. Preferably, thesupport arms 90, 92 each include a plurality of light sources 240. Thelight sources 240 (hereinafter collectively referred to as “light source240”) are shown in FIGS. 5 and 6 as a plurality of light emitting diodes(LED's). The support arms 90, 92 in the first (i.e., syringe-engagedposition) preferably extend laterally along lateral sides 242, 244 ofthe pressure jacket 32 and preferably substantially parallel to thecentral axis L of the syringe 24, which is also substantially thecentral axis of the pressure jacket 32. It has been found by theinventors that illumination along the central axis L of the syringe 24and, hence, the pressure jacket 32 provides the best diffusion of lightin the syringe body 70. Accordingly, the pressure jacket 32 ispreferably made of a substantially clear plastic material to allow lightto penetrate into the syringe body 70. As stated, the light source 240may be a plurality of light emitting diodes (LED's). However, anyequivalent lighting source may be used to replace the light emittingdiodes (LED's), such as a mini-fluorescent light bar 245, which isschematically illustrated in FIGS. 5 and 6. Another possible lightsource 240 is a fiber-optic bed. Additionally, the light source 240 maybe located on the syringe retaining member 106, facing the conicalportion 212 of the syringe 24. For example, the light source 240 may beattached to the syringe facing side 206′ of the syringe retaining member106′ shown in FIGS. 12-20.

[0120] Referring to FIGS. 5-8 and 23-26, to enter the fluid in thesyringe 24, light from the light source 240 must pass through a wall 246of the pressure jacket 32 and a body wall 248 of the syringe body 70. Adifficulty with illuminating cylindrical structures, such as thepressure jacket 32 and syringe body 70, with an externally located lightsource is that all areas of the cylindrical structure are notilluminated equally, particularly when the cylindrical structure isfilled with fluid. To assure adequate diffusion of light in the syringe24, the present invention includes one or more diffusion elementsengaged with or incorporated into the pressure jacket 32, which is usedto achieve proper light diffusion before light enters the syringe body70. In alternative embodiments, the diffusion element(s) may be placedon or incorporated into the inner or outer walls of the pressure jacket32, or embedded between the inner and outer walls. Several embodimentsof the pressure jacket 32 are discussed hereinafter with particularreference to FIGS. 23-26. The embodiments are separately designated withlower case letters “a”, “b”, and “c”.

[0121]FIG. 24 is a longitudinal cross sectional view of a firstlight-diffusing pressure jacket made in accordance with the presentinvention and designated with reference character 32 a. The pressurejacket 32 a includes a lens 260 located on an inner surface 262 of thepressure jacket wall 246. The lens 260 may be affixed to the innersurface 262 of the pressure jacket wall 246 with an adhesive, or formedintegrally with the pressure jacket wall 246. The lens 260 extendslongitudinally along the inner surface 262 of the pressure jacket wall246 and diffuses light entering the pressure jacket 32 a from the lightsource 240. Preferably, the lens 260 extends substantially the distancebetween the distal end 42 and proximal end 44 of the pressure jacket 32a. However, in alternative embodiments, the lens 260 could be segmentedor multiple lenses could be placed along the pressure jacket 32 a.Additionally, the lens 260 is preferably located on the inner surface262 directly opposite from the light source 240. Once passing throughthe lens 260, the light is diffused and enters the syringe body 70 tofully illuminate the fluid in the syringe body 70, without the presenceof “dead” or shaded areas, or “hotspots” of increased glare.

[0122] A second embodiment of the pressure jacket is shown in FIG. 25and is designated with reference character 32 b. In this embodiment, theinner surface 262 of the pressure jacket wall 246 is roughened or etchedto form a roughened or etched area 263. In particular, the inner surface262 of the pressure jacket wall 246 is chemically or mechanicallyroughened such that the roughened area 263 is formed in the originalclear surface finish. The degree or area of roughness may be made aswide as necessary to scatter or diffuse the light entering the syringebody 70 from the light source 240. The roughened area 263 may also besegmented and is preferably located substantially opposite from thelight source 240.

[0123]FIG. 26 shows a presently preferred embodiment of the pressurejacket, which is designated with reference character 32 c. The pressurejacket 32 c, according to this embodiment, includes a light-diffusingstrip 264 applied to the inner surface 262 of the pressure jacket wall246. The light-diffusing strip 264 may be affixed to the inner surface,for example, 262 with an adhesive. The light-diffusing strip 264 extendslongitudinally along the inner surface 262 of the pressure jacket wall246 and diffuses light entering the pressure jacket 32 c from the lightsource 240. Preferably, the light-diffusing strip 264 extendssubstantially the distance between the distal end 42 and the proximalend 44 of the pressure jacket 32 c. In alternative embodiments, however,the light-diffusing strip 264 may be segmented, or multiple strips couldbe placed along the pressure jacket. Additionally, the light-diffusingstrip 264 is preferably located on the inner surface 262 directlyopposite from the light source 240.

[0124] A preferred attachment scheme for the light-diffusing strip 264locates the light-diffusing strip 264 in a groove 266 (or grooves ifmore than one strip 264 is used) extending longitudinally along theinner surface 262 of the pressure jacket wall 246. The groove 266 ispreferably substantially trapezoidal shaped in cross section with twoinward facing projections 268, 270 for retaining the light-diffusingstrip 264 in the groove 266. Preferably, the light-diffusing strip 264is a white polycarbonate material. The width of the groove 266 andlight-diffusing strip 264 may be increased as necessary to fully diffusethe light entering the syringe body 70, as will be appreciated by thoseskilled in the art.

[0125] Referring to FIG. 27, as discussed previously, prior art syringesfor medical injection procedures, such as syringe 280, are often storedwith a pre-positioned syringe plunger 282. A difficulty with currentdisposable plastic syringes 280 is that these syringes 280 exhibitplastic creep over time and especially during sterilization heat cycles.This causes the plastic syringe 280 to swell, particularly in a plungerarea 284 about the syringe plunger 282. This often makes it difficult toload prior art plastic syringes 280 in front loading pressure jackets,because of swelling 286 in the plunger area 284 wherein the syringeplunger 282 is stored.

[0126] As shown in FIGS. 3, 20, 21, 28, and 29 the syringe 24 of thepresent invention overcomes this disadvantage by storing the syringeplunger 216 in the expansion section 78. The expansion section 78 ispreferably formed adjacent the cylindrical center section 80 of thesyringe body 70 and at the proximal end of 74 of the syringe body 70.However, the expansion section 78 may be formed or located at anyposition in the syringe body 70 wherein the syringe plunger 216 is to bestored. At the expansion section 78, the wall 248 of the syringe body 70narrows from a thickness t to a reduced wall thickness t_(r). Thus, aninner diameter ID_(es) of the expansion section 78 is larger than aninner diameter ID_(cs) of the cylindrical center section or main body80. The reduced wall thickness t_(r) at the expansion section 78 allowsthe expansion section 78 to expand outward under the force exerted bythe syringe plunger 216 without an outer diameter OD_(es) of theexpansion section 78 becoming larger than an outer diameter OD_(cs) ofthe center section 80 of the syringe body 70. As shown in FIGS. 20 and21, both an outer surface 290 of the wall 248 of the syringe body 70 andan inner surface 292 of the wall 248 of the syringe body 70 taper or arestepped to form the reduced wall thickness t_(r) at the expansionsection 78. In particular, the outer surface 290 of the wall 248 of thesyringe body 70 is tapered or stepped inward toward the central axis Lof the syringe body 70 and the inner surface 292 of the wall 248 of thesyringe body 70 tapers or is stepped outward away from the central axisL of the syringe body 70 to form the reduced wall thickness t_(r). Analternative configuration to the foregoing is to only taper or step theinner surface 292 of the wall 248 of the syringe body 70 outward awayfrom the central axis L of the syringe body 70. Another alternative isto only taper or step the outer surface 290.

[0127] The reduced wall thickness t_(r) at the expansion section 78 ofthe syringe 24 accommodates the expansion and plastic creep of theplastic syringe body 70 even after long periods of storage. Even afterlong storage periods, the syringe 24 with pre-positioned syringe plunger216 may be quickly and easily inserted into front-loading pressurejacket systems, such as the pressure jacket assemblies 30, 30′ discussedpreviously. As stated previously, the syringe plunger 216 is stored inthe expansion section 78. When the syringe 24 is inserted into thepressure jackets 32, 32′ and ready for use, the syringe plunger 216 isengaged by the injector drive piston 22 in the manner discussedpreviously and moved forward from the expansion section 78 to the centersection or main body 80 of the syringe 24, which may be referred to asthe “working zone” of the syringe 24.

[0128] Referring to FIGS. 30 and 31 (and FIGS. 4-6), an alternativeconnection between the pressure jacket(s) 32, 32′ and faceplate(s) 18,18′ is shown, as indicated previously. The alternative configurationillustrated in FIGS. 30 and 31 allows the pressure jacket(s) 32, 32′ tomove axially (i.e., distally and proximally) with respect to thefaceplate(s) 18, 18′. At higher pressures, the syringe supportstructure(s) 36, 36′ in the respective embodiments of the fluidinjection apparatus(es) 10, 10′ will move slightly distally forward dueto stretching of the support arms 90, 92 and 90′, 92′. This stretchingoccurs as the syringe 24 pushes forward on the syringe retainingmember(s) 106, 106′ in the syringe support structure(s) 36, 36′.Additionally, at higher pressures, the syringe 24 also swells andfrictionally engages the internal wall in the pressure jacket(s) 32,32′. The frictional engagement between the syringe 24 and, moreparticularly, the main body 80 of the syringe 24, and the internal wallof the pressure jacket(s) 32, 32′ pulls the pressure jacket(s) 32, 32′forward with the syringe 24. If the pressure jacket(s) 32, 32′ is notpermitted to move forward an incremental amount, a stick-slip routinedevelops, wherein the syringe 24 is held back temporarily by frictionalforce until this is overcome. Thereafter, the syringe 24 slips forwardand impacts against the syringe retaining member(s) 106, 106′.

[0129] The arrangement in FIGS. 30 and 31 attaches the pressurejacket(s) 32, 32′ directly to the faceplate(s) 18, 18′, as indicatedpreviously. The pressure jackets(s) 32, 32′ may be formed with thebayonet projections 54, 56, and 54′, 56′ at the proximal end(s) 44, 44′for cooperating with the opposing recesses 60, 62 and 60′, 62′ and thebayonet receiving slots 64, 66 and 64′, 66′ in the faceplate(s) 18, 18′.However, the bayonet receiving slots 64, 66 and 64′, 66′ are nowpreferably formed to allow the proximal end(s) 44, 44′ of the pressurejackets 32, 32′ to move axially a small distance in the slots 64, 66 and64′, 66′, and avoid the stick-slip problem discussed previously. Only asmall axial distance “A” is necessary to relieve the stick-slip problem.For example, this axial distance may be about 0.050 inches.

[0130] While the present invention was described with reference topreferred embodiments of the fluid injection apparatus and syringe usedtherewith, those skilled in the art may make modifications andalterations to the present invention without departing from the scopeand spirit of the invention. Accordingly, the above detailed descriptionis intended to be illustrative rather than restrictive. The invention isdefined by the appended claims, and all changes to the invention thatfall within the meaning and range of equivalency of the claims are to beembraced within their scope.

What is claimed is:
 1. A fluid injection apparatus for use with asyringe having an injection section with an injection neck, the fluidinjection apparatus comprising: a housing defining an opening and adrive piston extendable through the opening for imparting motive forcesto a syringe plunger disposed within the syringe; and a pressure jacketassembly associated with the housing for securing the syringe during aninjection procedure, the pressure jacket assembly comprising: a pressurejacket associated with the housing and aligned with the opening; atleast one support arm associated with and extending outward from thehousing; and a syringe retaining member associated with the at least onesupport arm, the syringe retaining member defining a syringe receivingslot for receiving the injection neck of the syringe and viewing atleast a portion of the injection section of the syringe, the at leastone support arm movable selectively between a first position wherein thesyringe retaining member prevents removal of the syringe from thepressure jacket and a second position wherein the syringe is removablefrom the pressure jacket.
 2. The fluid injection apparatus of claim 1,wherein the pressure jacket has a distal end defining a syringereceiving opening for receiving the syringe and a proximal endassociated with the housing.
 3. The fluid injection apparatus of claim1, further comprising a faceplate associated with the housing, thefaceplate defining a passage aligned with the opening and through whichthe drive piston is extendable.
 4. The fluid injection apparatus ofclaim 1, wherein the drive piston further comprises an axially directedlight source for illuminating the syringe.
 5. The fluid injectionapparatus of claim 1, wherein the pressure jacket is removablyassociated with a faceplate connected to the housing.
 6. The fluidinjector apparatus of claim 1, wherein the pressure jacket assemblyfurther comprises a coupling member adapted to removably associate thepressure jacket with a faceplate connected to the housing.
 7. The fluidinjection apparatus of claim 6, wherein the pressure jacket is removablyassociated with the coupling member by a threaded connection.
 8. Thefluid injection apparatus of claim 6, wherein the coupling member isremovably associated with the faceplate by a bayonet socket connection.9. The fluid injection apparatus of claim 1, wherein the at least onesupport arm comprises a pair of support arms adapted to support thesyringe retaining member, the support arms each having a distal end anda proximal end.
 10. The fluid injection apparatus of claim 9, whereinthe support arms pivotally support the syringe retaining member.
 11. Thefluid injection apparatus of claim 9, further comprising an axleassembly adapted to connect the proximal ends of the support armstogether in the housing and configured to selectively move the supportarms between the first and second positions.
 12. The fluid injectionapparatus of claim 9, wherein the support arms extend laterally alonglongitudinal sides of the pressure jacket in the first position.
 13. Thefluid injection apparatus of claim 9, wherein at least one of thesupport arms comprises at least one light source positioned toilluminate the syringe received in the pressure jacket.
 14. The fluidinjection apparatus of claim 9, wherein the syringe retaining membercomprises at least one light source positioned to illuminate the syringereceived in the pressure jacket.
 15. The fluid injection apparatus ofclaim 9, wherein the axle assembly comprises an axle linkage extendingbetween the proximal ends of the support arms, the axle linkagecomprising a base member and two outward extending axles.
 16. The fluidinjection apparatus of claim 15, wherein the base member defines arecess through which the drive piston is extendable and retractable inany position of the support arms.
 17. The fluid injection apparatus ofclaim 1 wherein the proximal ends of the support arms each define acircular aperture, and wherein the axle assembly comprises an axlelinkage and a pair of circular members rotatably received in thecircular apertures, respectively, the circular members supported on theaxle linkage.
 18. The fluid injection apparatus of claim 17, wherein acentral axis of the axle linkage is offset from a rotational axis of thecircular members for converting rotational movement of the circularmembers to translational movement of the support arms.
 19. The fluidinjection apparatus of claim 18, wherein the axle linkage is supportedon a faceplate associated with the housing by a pair of supportbrackets, the circular members associated with the support brackets,respectively, to limit the rotational movement of the circular membersin the circular apertures.
 20. The fluid injection apparatus of claim19, wherein the circular members each comprise a ball detent adapted fora mating connection with detent openings defined in the support bracketsfor providing at least a tactile indication that the support arms are inthe first position.
 21. The fluid injection apparatus of claim 9,wherein the proximal ends of the support arms are associated with afaceplate connected to the housing to guide the movement of the supportarms between the first and second positions.
 22. The fluid injectionapparatus of claim 21, wherein the proximal ends of the support armsdefine guide tracks and the faceplate comprises cross pins cooperatingwith the guide tracks, respectively, to guide the movement of thesupport arms between the first and second positions.
 23. The fluidinjection apparatus of claim 9, further comprising a faceplate connectedto the housing, the faceplate comprising a pair of ball detents adaptedfor a mating connection with detent openings defined in the proximalends of the support arms, respectively, to prevent uncontrolled movementof the support arms to the second position.
 24. The fluid injectionapparatus of claim 1, wherein the at least one support arm comprises atleast one light source positioned to illuminate the syringe received inthe pressure jacket.
 25. The fluid injection apparatus of claim 1,wherein the syringe retaining member comprises at least one light sourcepositioned to illuminate the syringe received in the pressure jacket.26. The fluid injection apparatus of claim 1, wherein the pressurejacket is removably associated with a faceplate connected to thehousing, and movable axially with respect to the faceplate.
 27. Thefluid injection apparatus of claim 1, wherein the at least one supportarm extends laterally along a longitudinal side of the pressure jacketin the first position.
 28. The fluid injection apparatus of claim 1,wherein the pressure jacket is made of substantially clear plastic. 29.The fluid injection apparatus of claim 29, wherein the pressure jacketcomprises a light-diffusing device for diffusing light from a lightsource external to the pressure jacket.
 30. A fluid injection apparatusfor use with a syringe, the fluid injection apparatus comprising: ahousing; and a pressure jacket assembly associated with the housing forsecuring the syringe during an injection procedure, the pressure jacketassembly comprising: a pressure jacket associated with the housing; atleast one support arm extending outward from the housing; and at leastone light source associated with the at least one support arm andpositioned to illuminate the syringe received in the pressure jacket.31. The fluid injection apparatus of claim 30, wherein the light sourceis selected from the group consisting of light emitting diodes, amini-fluorescent light bar, and a fiber-optic bed.
 32. The fluidinjection apparatus of claim 30, wherein the at least one support armcomprises a pair of support arms, and wherein at least one of thesupport arms comprises the at least one light source.
 33. The fluidinjection apparatus of claim 32, wherein the support arms are movablebetween a first position extending laterally along longitudinal sides ofthe pressure jacket and a second position depending below the pressurejacket, such that in the first position of the support arms the syringeis illuminated substantially along a central axis thereof.
 34. The fluidinjection apparatus of claim 32, wherein the at least one light sourceis selected from the group consisting of a plurality of light emittingdiodes, a mini-florescent bar, and a fiber-optic bed.
 35. The fluidinjection apparatus of claim 30, further comprising a light-diffusingdevice associated with the pressure jacket for diffusing light passingthrough the wall of the pressure jacket.
 36. The fluid injectionapparatus of claim 35, wherein the light-diffusing device is associatedwith an inner surface or an outer surface of the pressure jacket. 37.The fluid injection apparatus of claim 35, wherein the light-diffusingdevice is disposed between an inner surface and an outer surface of thepressure jacket.
 38. The fluid injection apparatus of claim 35, whereinthe light-diffusing device comprises a lens.
 39. The fluid injectionapparatus of claim 38, wherein the lens extends longitudinally along aninner surface of the pressure jacket.
 40. The fluid injection apparatusof claim 35, wherein the light-diffusing device comprises an etched areaformed on the pressure jacket.
 41. The fluid injection apparatus ofclaim 40, wherein the etched area extends longitudinally along an innersurface of the pressure jacket.
 42. The fluid injection apparatus ofclaim 35, wherein the light-diffusing device comprises a light-diffusingstrip.
 43. The fluid injection apparatus of claim 42, wherein thelight-diffusing strip comprises white polycarbonate material.
 44. Thefluid injection apparatus of claim 30, wherein the wall of the pressurejacket defines a groove in an inner surface thereof, and wherein thepressure jacket assembly comprises a light-diffusing strip disposed inthe groove for diffusing light passing through the wall of the pressurejacket.
 45. The fluid injection apparatus of claim 44, wherein thelight-diffusing strip comprises white polycarbonate material.
 46. Thefluid injection apparatus of claim 44, wherein the groove is trapezoidalshaped in cross section having two inward facing projections forretaining the light-diffusing strip in the groove.
 47. The fluidinjection apparatus of claim 44, wherein the groove extendslongitudinally along the inner surface of the pressure jacket.
 48. Thefluid injection apparatus of claim 30, wherein the pressure jacket ismade of substantially clear plastic.
 49. The fluid injection apparatusof claim 48, wherein the substantially clear plastic is selected fromthe group consisting of polypropylene, polyethylene, and polycarbonate.50. A fluid injection apparatus, comprising: a syringe, comprising: acylindrical body with an injection section comprising a conical portionand an injection neck, the conical portion defining an alignment flange;and a syringe plunger movably received in the body and having a couplingend comprising a pair of coupling members defining a slot therebetween,the slot substantially aligned with the alignment flange such that thealignment flange provides an indication of the orientation of the slot;and an injector, comprising: a housing defining an opening and a drivepiston extendable through the opening for imparting motive forces to thesyringe plunger disposed within the body; and a pressure jacket assemblyassociated with the housing for securing the syringe during an injectionprocedure, the pressure jacket assembly comprising a pressure jacketassociated with the housing and aligned with the opening, at least onesupport arm associated with and extending outward from the housing, anda syringe retaining member associated with the at least one support arm,the syringe retaining member defining a syringe receiving slot forreceiving the injection neck of the syringe and viewing at least aportion of the injection section, the at least one support arm movableselectively between a first position wherein the syringe retainingmember prevents removal of the syringe from the pressure jacket and asecond position wherein the syringe is removable from the pressurejacket; wherein alignment of the alignment flange with the syringereceiving slot in the syringe retaining member orients the couplingmembers in a desired mounting position oriented to receive the drivepiston.
 51. The fluid injection apparatus of claim 50, wherein theconical portion further comprises a light-sensitive fluid dot as anoptical aid.
 52. The fluid injection apparatus of claim 50, wherein thealignment flange extends outward sufficiently from the conical portionto be grasped by a user of the syringe and used as a handle formanipulating the syringe.
 53. The fluid injection apparatus of claim 50,wherein the coupling members each have an inward projecting engagementarm for engaging the drive piston.
 54. The fluid injection apparatus ofclaim 50, wherein the coupling members comprise flexible couplingmembers.
 55. A pressure jacket for use with a syringe used in a fluidinjection procedure, comprising: an elongated body formed ofsubstantially clear plastic; and a light-diffusing device provided onthe body and adapted to diffuse light passing therethrough emitted by anexternally located light source.
 56. The pressure jacket of claim 55,wherein the light-diffusing device comprises a lens.
 57. The pressurejacket of claim 56, wherein the lens extends longitudinally along aninner surface of the body.
 58. The pressure jacket of claim 55, whereinthe light-diffusing device comprises an etched area on the body.
 59. Thepressure jacket of claim 58, wherein the etched area extendslongitudinally along an inner surface of the body.
 60. The pressurejacket of claim 55, further comprising a groove defined in an innersurface of the body, and the light-diffusing device comprising alight-diffusing strip disposed in the groove.
 61. The pressure jacket ofclaim 60, wherein the groove extends longitudinally along the innersurface of the body.
 62. The pressure jacket of claim 60, wherein thelight-diffusing strip comprises white polycarbonate material.
 63. Thepressure jacket of claim 60, wherein the groove is trapezoidal shaped incross section having two inward facing projections for retaining thelight-diffusing strip in the groove.
 64. The pressure jacket of claim55, wherein the substantially clear plastic is selected from the groupconsisting of polypropylene, polyethylene, and polycarbonate.
 65. Asyringe, comprising: a cylindrical main body, a conical portionconnected to the main body, and a discharge outlet connected to theconical portion; a plunger movably disposed within at least a portion ofthe main body; and an alignment flange disposed on and extending outwardfrom at least a portion of the conical portion, the alignment flangedefining a hollow area therein.
 66. The syringe of claim 65, wherein theplunger has a coupling end comprising a pair of coupling membersdefining a slot therebetween, the slot substantially aligned with thealignment flange such that the alignment flange provides an indicationof the orientation of the slot.
 67. The syringe of claim 66, wherein thecoupling members comprise flexible coupling members.
 68. The syringe ofclaim 65, wherein the conical portion further comprises alight-sensitive fluid dot as an optical aid.
 69. The syringe of claim65, wherein the alignment flange extends outward sufficiently from theconical portion to be grasped by a user of the syringe and used as ahandle for manipulating the syringe.
 70. A syringe, comprising: a bodyhaving a distal end and a proximal end, the body comprising an injectionsection at the distal end and an expansion section at the proximal end,the injection section and the expansion section connected by a centersection of relatively uniform outer diameter; and wherein a wallthickness of the body narrows to a reduced wall thickness at theexpansion section such that an inner diameter of the expansion sectionis larger than the inner diameter of the center section for allowing theexpansion section to expand when a plunger is disposed in the expansionsection.
 71. The syringe of claim 70, wherein the reduced wall thicknessallows the expansion section to expand to an outer diameter no greaterthan approximately the outer diameter of the center section when theplunger is disposed in the expansion section.
 72. The syringe of claim70, wherein the body is made of a deformable material permitting theexpansion section to expand to an outer diameter no greater thanapproximately the outer diameter of the center section when the plungeris disposed in the expansion section.
 73. The syringe of claim 70,wherein an outer surface of the body is tapered or stepped inward towarda central axis of the body and an inner surface of the body is taperedor stepped outward away from the central axis of the body to form thereduced wall thickness.
 74. The syringe of claim 70, wherein at leastone of an outer surface of the body is tapered or stepped inward towarda central axis of the body and an inner surface of the body is taperedor stepped outward away from the central axis of the body to form thereduced wall thickness.
 75. A syringe, comprising: a body having adistal end and a proximal end, the body comprising an injection sectionat the distal end and an expansion section at the proximal end, theinjection section and the expansion section connected by a centersection of relatively uniform outer diameter; and a plunger movablyreceived in the body and seated for storage in the expansion section;and wherein a wall thickness of the body narrows to a reduced wallthickness at the expansion section such that an inner diameter of theexpansion section is larger than the inner diameter of the centersection allowing the expansion section to expand under radial outwardforce exerted by the plunger.
 76. The syringe of claim 75, wherein thereduced wall thickness allows the expansion section to expand to anouter diameter no greater than approximately the outer diameter of thecenter section when the plunger is seated in the expansion section. 77.The syringe of claim 75, wherein the body is made of a deformablematerial permitting the expansion section to expand to an outer diameterno greater than approximately the outer diameter of the center sectionwhen the plunger is seated in the expansion section.
 78. The syringe ofclaim 75, wherein an outer surface of the body is tapered or steppedinward toward a central axis of the body and an inner surface of thebody is tapered or stepped outward away from the central axis of thebody to form the reduced wall thickness.
 79. The syringe of claim 75,wherein at least one of an outer surface of the body is tapered orstepped inward toward a central axis of the body and an inner surface ofthe body is tapered or stepped outward away from the central axis of thebody to form the reduced wall thickness.
 80. The syringe of claim 75,wherein the injection section comprises a conical portion and aninjection neck, and wherein the conical portion comprises an alignmentflange extending outward from at least a portion of the conical portion,the alignment flange defining a hollow area therein.
 81. The syringe ofclaim 80, wherein the plunger has a coupling end comprising a pair ofcoupling members defining a slot therebetween.
 82. The syringe of claim81, wherein the slot defined between the coupling members issubstantially aligned with the alignment flange such that the alignmentflange provides an indication of the orientation of the slot.
 83. Thesyringe of claim 81, wherein the coupling members comprise flexiblecoupling members.
 84. The syringe of claim 80, wherein the conicalportion further comprises a light-sensitive fluid dot as an optical aid.85. A syringe, comprising: a cylindrical body having a distal end and aproximal end, the body comprising an injection section at the distal endand an expansion section at the proximal end, the injection section andexpansion section connected by a cylindrical center section ofrelatively uniform outer diameter, the injection section comprising aconical portion and an injection neck, the conical portion comprising analignment flange extending outward from at least a portion of theconical portion; a plunger movably received in the body and having acoupling end with a pair of flexible coupling members defining a slottherebetween for engaging a drive piston of an injector, the slotsubstantially aligned with the alignment flange such that the alignmentflange provides an indication of the orientation of the slot, theplunger seated for storage in the expansion section; wherein a wallthickness of the body narrows to a reduced wall thickness at theexpansion section such that an inner diameter of the expansion sectionis larger than the inner diameter of the center section for allowing theexpansion section to expand under radial outward force exerted by theplunger.
 86. The syringe of claim 85, wherein the reduced wall thicknessallows the expansion section to expand to an outer diameter no greaterthan approximately the outer diameter of the center section under theradial outward force exerted by the plunger.
 87. The syringe of claim85, wherein the body is made of a deformable material permitting theexpansion section to expand to an outer diameter no greater thanapproximately the outer diameter of the center section under the radialoutward force exerted by the plunger.
 88. The syringe of claim 85,wherein the body is made of substantially clear plastic selected fromthe group consisting of polypropylene, polyethylene, and polycarbonate.89. The syringe of claim 85, wherein an outer surface of the body istapered or stepped inward toward a central axis of the body and an innersurface of the body is tapered or stepped outward away from the centralaxis of the body to form the reduced wall thickness.
 90. The syringe ofclaim 85, wherein at least one of an outer surface of the body istapered or stepped inward toward a central axis of the body and an innersurface of the body is tapered or stepped outward away from the centralaxis of the body to form the reduced wall thickness.
 91. The syringe ofclaim 85, wherein the coupling members each have an inward projectingengagement arm for engaging the drive piston.
 92. The syringe of claim85, wherein the alignment flange extends outward sufficiently from theconical portion to be grasped by a user of the syringe and used as ahandle for manipulating the syringe.
 93. A method of loading a syringecomprising a cylindrical main body, a conical portion connected to themain body, and a discharge outlet connected to the conical portion, aplunger movably disposed within at least a portion of the main body, andan alignment flange extending outward from at least a portion of theconical portion, to an injector comprising a pressure jacket assemblycomprising a pressure jacket associated with the injector, at least onesupport arm associated with and extending outward from the injector, anda syringe retaining member associated with the at least one support arm,the syringe retaining member defining a syringe receiving slot forreceiving the discharge outlet of the syringe, the at least one supportarm movable between a first position wherein the syringe retainingmember prevents removal of the syringe from the pressure jacket and asecond position wherein the syringe is removable from the pressurejacket, the method comprising: inserting a proximal end of the syringeinto the pressure jacket; aligning the alignment flange on the syringewith the syringe receiving slot in the syringe retaining member; andmoving the at least one support arm and syringe retaining member fromthe second position to the first position.
 94. The method of claim 93,further comprising: moving the at least one support arm and the syringeretaining member from the first position to the second position; andremoving the syringe from the pressure jacket.
 95. The method of claim93, further comprising: connecting the plunger to a drive piston of theinjector; and advancing the drive piston to move the plunger within thesyringe.
 96. The method of claim 95, further comprising retracting theplunger within the syringe with the drive piston.
 97. A fluid injectionapparatus for use with a syringe having a syringe body and an injectionsection with an injection neck, the fluid injection apparatuscomprising: a housing defining an opening and a drive piston extendablethrough the opening for imparting motive forces to a syringe plungerdisposed within the syringe; and a pressure jacket assembly associatedwith the housing for securing the syringe during an injection procedure,the pressure jacket assembly comprising: a pressure jacket associatedwith the housing and aligned with the opening; at least one support armpivotally associated with and extending outward from the housing; and asyringe retaining member pivotally associated with the at least onesupport arm, the syringe retaining member defining a syringe receivingslot for receiving the injection neck of the syringe and viewing atleast a portion of the injection section, the at least one support armmovable between a first position wherein the syringe retaining memberprevents removal of the syringe from the pressure jacket and a secondposition wherein the syringe is removable from the pressure jacket. 98.The fluid injection apparatus of claim 97, wherein the syringe retainingmember is pivotal between a syringe retaining position cooperating withthe injection section of the syringe and preventing removal of thesyringe from the pressure jacket and a pivoted position disengagedsufficiently from the injection section to allow the at least onesupport arm to pivot to the second position.
 99. The fluid injectionapparatus of claim 97, wherein the at least one support arm comprises aproximal end pivotally associated with the housing and a distal endextending outward from the housing, the proximal end having an increasedcross section relative to the distal end such that an upward moment iscreated about the pivotal association with the housing for maintainingthe at least one support arm in the first position.
 100. The fluidinjection apparatus of claim 97, further comprising a spring actingbetween the syringe retaining member and the at least one support armfor orienting the syringe retaining member with respect to the at leastone support arm.
 101. The fluid injection apparatus of claim 100,wherein the spring is adapted to bias the syringe retaining member to aposition substantially perpendicular to the at least one support arm.102. The fluid injection apparatus of claim 100, wherein the spring isselected from the group consisting of a leaf spring, a coil spring, anda torsion spring.
 103. The fluid injection apparatus of claim 100,wherein the spring is positioned in a cavity defined in the syringeretaining member adjacent a distal end of the at least one support arm.104. The fluid injection apparatus of claim 97, wherein the at least onesupport arm comprises a pair of support arms each having a proximal endpivotally associated with the housing and a distal end extending outwardfrom the housing, the proximal ends of the support arms having increasedcross sections relative to the distal ends such that an upward moment iscreated about the pivotal associations with the housing for maintainingthe support arms in the first position.
 105. The fluid injectionapparatus of claim 104, wherein the syringe retaining member ispivotally connected to the distal ends of the support arms andinterconnects the distal ends of the support arms
 106. The fluidinjection apparatus of claim 104, further comprising a pair of springsacting between the support arms, respectively, and the syringe retainingmember for orienting the syringe retaining member with respect to thesupport arms.
 107. The fluid injection apparatus of claim 106, whereinthe springs are adapted to bias the syringe retaining member to aposition substantially perpendicular to the support arms.
 108. The fluidinjection apparatus of claim 106, wherein the springs are selected fromthe group consisting of a leaf spring, a coil spring, and a torsionspring.
 109. The fluid injection apparatus of claim 106, wherein thesprings are positioned in respective cavities defined in the syringeretaining member adjacent the distal ends of the support arms.
 110. Thefluid injection apparatus of claim 97, wherein the drive piston furthercomprises an axially directed light source for illuminating the syringe.111. The fluid injection apparatus of claim 97, wherein the at least onesupport arm is pivotally connected to a faceplate connected to thehousing.
 112. The fluid injection apparatus of claim 97, wherein thepressure jacket is removably associated with a faceplate connected tothe housing.
 116. The fluid apparatus of claim 97, wherein the pressurejacket assembly further comprises a coupling member adapted to removablyassociate the pressure jacket with the faceplate.
 117. The fluidinjection apparatus of claim 116, wherein the pressure jacket isremovably associated with the coupling member by a threaded connection.118. The fluid injection apparatus of claim 116, wherein the couplingmember is removably associated with the faceplate by a bayonet socketconnection.
 119. The fluid injection apparatus of claim 97, wherein thepressure jacket has a distal end defining a syringe receiving openingfor receiving the syringe, the distal end of the pressure jacketdefining a beveled portion forming an acute angle with a central axis ofthe pressure jacket.
 120. The fluid injection apparatus of claim 119,wherein the syringe retaining member has a syringe facing side formed tocooperate with the injection section of the syringe, and wherein withthe at least one support arm in the first position the syringe retainingmember is pivotal between a syringe retaining position wherein thesyringe facing side cooperates substantially with the injection sectionpreventing removal of the syringe from the pressure jacket, and apivoted position pivoted away from the injection section and toward thebeveled position for allowing the at least one support arm to pivot tothe second position.
 121. The fluid injection apparatus of claim 119,wherein the beveled portion defines an acute angle of about 60° or lesswith the central axis of the pressure jacket.
 122. The fluid injectionapparatus of claim 97, wherein the at least one support arm comprises atleast one light source positioned to illuminate the syringe received inthe pressure jacket.
 123. The fluid injection apparatus of claim 97,wherein the at least one support arm comprises a pair of support arms,the support arms pivotally supporting the syringe retaining member, atleast one of the support arms comprising at least one light sourcepositioned to illuminate the syringe received in the pressure jacket.124. The fluid injection apparatus of claim 123, wherein the supportarms extend laterally along longitudinal sides of the pressure jacket inthe first position.
 125. The fluid injection apparatus of claim 97,wherein the syringe retaining member comprises at least one light sourcepositioned to illuminate the syringe received in the pressure jacket.126. The fluid injection apparatus of claim 97, wherein the pressurejacket is removably associated with a faceplate connected to thehousing, and movable axially with respect to the faceplate.
 127. Thefluid injection apparatus of claim 97, wherein the at least one supportarm extends laterally along a longitudinal side of the pressure jacketin the first position.
 128. The fluid injection apparatus of claim 97,wherein the pressure jacket is made of substantially clear plastic. 129.The fluid injection apparatus of claim 128, wherein the substantiallyclear plastic is selected from the group consisting of polypropylene,polyethylene, and polycarbonate.
 130. The fluid injection apparatus ofclaim 97, wherein the pressure jacket comprises a light-diffusing devicefor diffusing light from a light source external to the pressure jacket.